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Comm object for Microsoft Word is not populated when Visual Studio is started with Admin Privileges

What I Want to achieve is to get file opened in Microsoft Word using C#. I have tried the following code and its working fine. But when i start Visual Studio 2019 with administrator privileges and try the same code, it doesn't work.
Here is my code
using System;
using System.Collections;
using System.Diagnostics;
using System.Runtime.InteropServices;
using System.Runtime.InteropServices.ComTypes;
using System.Text;
namespace ConsoleApp2
{
class Program
{
#region OLE32 Methods
[DllImport("ole32.dll")]
static extern int GetRunningObjectTable(int reserved, out IRunningObjectTable prot);
[DllImport("ole32.dll")]
static extern int CreateBindCtx(uint reserved, out IBindCtx ppbc);
#endregion
static void Main(string[] args)
{
try
{
Console.WriteLine($"File Name: {GetFileName()}");
Console.ReadLine();
}
catch (Exception ex)
{
Console.WriteLine($"Error:{ex.Message}");
}
}
public static string GetFileName()
{
IRunningObjectTable runningObjectTable;
GetRunningObjectTable(0, out runningObjectTable);
dynamic objValue = GetRunningInstances("Word.Application", runningObjectTable);
if (objValue == null)
{
Console.WriteLine($"Word Application reference not found");
return string.Empty;
}
else
{
Console.WriteLine($"Word Application reference found");
}
dynamic propValue = objValue.ActiveWindow;
if (propValue == null) return string.Empty;
propValue = objValue.ActiveDocument;
if (propValue == null) return string.Empty;
string fileName = propValue.FullName ?? string.Empty;
return fileName;
}
static object GetRunningInstances(string progId, IRunningObjectTable Rot)
{
string clsId = null;
Type type = Type.GetTypeFromProgID(progId);
if (type != null)
clsId = type.GUID.ToString().ToUpper();
if (Rot == null)
return null;
// get enumerator for ROT entries
IEnumMoniker monikerEnumerator = null;
Rot.EnumRunning(out monikerEnumerator);
if (monikerEnumerator == null)
return null;
monikerEnumerator.Reset();
object instance = null;
IntPtr pNumFetched = new IntPtr();
IMoniker[] monikers = new IMoniker[1];
// go through all entries and identifies app instances
while (monikerEnumerator.Next(1, monikers, pNumFetched) == 0)
{
IBindCtx bindCtx;
CreateBindCtx(0, out bindCtx);
if (bindCtx == null)
continue;
string displayName;
monikers[0].GetDisplayName(bindCtx, null, out displayName);
if (displayName.ToUpper().IndexOf(clsId) > 0)
{
object ComObject;
Rot.GetObject(monikers[0], out ComObject);
if (ComObject == null)
continue;
instance = ComObject;
break;
}
}
return instance;
}
}
}
Environment I am using is
Visual Studio: 2019 v16.8.2
Target Framework:net5.0-windows
Project Type: Console
Steps to reproduce
Create a Console App Project and paste the above code in program.cs
open any file in Microsoft Word and run the app, it will display the path of the file opened in MS Word
Close Visual Studio, Open again with Administrative privileges and run the same project again, code will be unable to get path of the opened file.
Any Help will be appreciated.

Based on my test, I reproduced your problem. It is related to the GetRunningObjectTable method.
When we start the visual studio as the admin privileges, we only can see the processes that belongs to the admin. Of course, it also applies to standard users.
Therefore, when you use admin privileges for vs and standard privileges for ms-word, the parameter runningObjectTable will return null.
If you want to know more the details about the reason, you can refer to Understanding the Running Object Table.
Finally, if you want to get the correct result when you start vs with admin privileges, you also need start the word file with admin privileges. According to my test, it can get the correct result.

Unity Add Default Namespace to Script Template?

I just found Unity's script template for C# scripts. To get the script name you write #SCRIPTNAME# so it looks like this:
using UnityEngine;
using System.Collections;
public class #SCRIPTNAME# : MonoBehaviour
{
void Start ()
{
}
void Update ()
{
}
}
Then it would create the script with the right name, but is there something like #FOLDERNAME# so that I can put it in the right namespace directly when creating the script?

There is no built-in template variables like #FOLDERNAME#.
According to this post, there are only 3 magic variables.
"#NAME#"
"#SCRIPTNAME#"
"#SCRIPTNAME_LOWER#"
But you can always hook into the creation process of a script and append the namespace yourself using AssetModificationProcessor.
Here is an example that adds some custom data to the created script.
//Assets/Editor/KeywordReplace.cs
using UnityEngine;
using UnityEditor;
using System.Collections;
public class KeywordReplace : UnityEditor.AssetModificationProcessor
{
public static void OnWillCreateAsset ( string path )
{
path = path.Replace( ".meta", "" );
int index = path.LastIndexOf( "." );
string file = path.Substring( index );
if ( file != ".cs" && file != ".js" && file != ".boo" ) return;
index = Application.dataPath.LastIndexOf( "Assets" );
path = Application.dataPath.Substring( 0, index ) + path;
file = System.IO.File.ReadAllText( path );
file = file.Replace( "#CREATIONDATE#", System.DateTime.Now + "" );
file = file.Replace( "#PROJECTNAME#", PlayerSettings.productName );
file = file.Replace( "#SMARTDEVELOPERS#", PlayerSettings.companyName );
System.IO.File.WriteAllText( path, file );
AssetDatabase.Refresh();
}
}

I know it's and old question but in newer versions of Unity you can define a root namespace to be used in the project.
You can define the namespace in Edit > Project Settings > Editor > Root Namespace
Doing this will add the defined namespace on newly created scripts.

Using zwcloud's answer and some other resources I was able to generate a namespace on my script files:
First step, navigate:
Unity's default templates can be found under your Unity installation's directory in Editor\Data\Resources\ScriptTemplates for Windows and /Contents/Resources/ScriptTemplates for OSX.
And open the file 81-C# Script-NewBehaviourScript.cs.txt
And make the following change:
namespace #NAMESPACE# {
At the top and
}
At the bottom. Indent the rest so that the whitespace is as desired. Don't save this just yet. If you wish, you can make other changes to the template, such as removing the default comments, making Update() and Start() private, or even removing them entirely.
Again, do not save this file yet or Unity will throw an error on the next step. If you saved, just hit ctrl-Z to undo and then resave, then ctrl-Y to re-apply the changes.
Now create a new script inside an Editor folder inside your Unity Assets directory and call it AddNameSpace. Replace the contents with this:
using UnityEngine;
using UnityEditor;
public class AddNameSpace : UnityEditor.AssetModificationProcessor {
public static void OnWillCreateAsset(string path) {
path = path.Replace(".meta", "");
int index = path.LastIndexOf(".");
if(index < 0) return;
string file = path.Substring(index);
if(file != ".cs" && file != ".js" && file != ".boo") return;
index = Application.dataPath.LastIndexOf("Assets");
path = Application.dataPath.Substring(0, index) + path;
file = System.IO.File.ReadAllText(path);
string lastPart = path.Substring(path.IndexOf("Assets"));
string _namespace = lastPart.Substring(0, lastPart.LastIndexOf('/'));
_namespace = _namespace.Replace('/', '.');
file = file.Replace("#NAMESPACE#", _namespace);
System.IO.File.WriteAllText(path, file);
AssetDatabase.Refresh();
}
}
Save this script as well as saving the changes to 81-C# Script-NewBehaviourScript.cs.txt
And you're done! You can test it by creating a new C# script inside any series of folders inside Assets and it will generate the new namespace definition we created.

I'm well aware that this question has been answered by the awesome people (zwcloud, Darco18 and Alexey).
However, since my namespace organization follows the folder structure in the project, I've put together in a jiffy some minor modification to the code, and I'm sharing it here in case someone needs it and has the same organizational methodology which I'm following.
Please keep in mind that you need to set the root namespace in your project settings in the C# project generation section.
EDIT: I've adjusted the code a bit work with placement in the root folders of Scripts, Editor, etc..
public class NamespaceResolver : UnityEditor.AssetModificationProcessor
{
public static void OnWillCreateAsset(string metaFilePath)
{
var fileName = Path.GetFileNameWithoutExtension(metaFilePath);
if (!fileName.EndsWith(".cs"))
return;
var actualFile = $"{Path.GetDirectoryName(metaFilePath)}\\{fileName}";
var segmentedPath = $"{Path.GetDirectoryName(metaFilePath)}".Split(new[] { '\\' }, StringSplitOptions.None);
var generatedNamespace = "";
var finalNamespace = "";
// In case of placing the class at the root of a folder such as (Editor, Scripts, etc...)
if (segmentedPath.Length <= 2)
finalNamespace = EditorSettings.projectGenerationRootNamespace;
else
{
// Skipping the Assets folder and a single subfolder (i.e. Scripts, Editor, Plugins, etc...)
for (var i = 2; i < segmentedPath.Length; i++)
{
generatedNamespace +=
i == segmentedPath.Length - 1
? segmentedPath[i]
: segmentedPath[i] + "."; // Don't add '.' at the end of the namespace
}
finalNamespace = EditorSettings.projectGenerationRootNamespace + "." + generatedNamespace;
}
var content = File.ReadAllText(actualFile);
var newContent = content.Replace("#NAMESPACE#", finalNamespace);
if (content != newContent)
{
File.WriteAllText(actualFile, newContent);
AssetDatabase.Refresh();
}
}
}

OK, so this question was already answered by two wonderful people, zwcloud and Draco18s, and their solution works, I'm just showing another version of the same code that, I hope, will be a little more clear in terms of what exactly happening.
Quick notes:
Yes, in this method we are getting not the actual file path,
but the path of its meta file as a parameter
No, you can not use AssetModificationProcessor without UnityEditor prefix, it is deprecated
OnWillCreateAsset method is not shown via Ctrl+Shift+M, 'override' typing or base class metadata
_
using UnityEditor;
using System.IO;
public class ScriptTemplateKeywordReplacer : UnityEditor.AssetModificationProcessor
{
//If there would be more than one keyword to replace, add a Dictionary
public static void OnWillCreateAsset(string metaFilePath)
{
string fileName = Path.GetFileNameWithoutExtension(metaFilePath);
if (!fileName.EndsWith(".cs"))
return;
string actualFilePath = $"{Path.GetDirectoryName(metaFilePath)}{Path.DirectorySeparatorChar}{fileName}";
string content = File.ReadAllText(actualFilePath);
string newcontent = content.Replace("#PROJECTNAME#", PlayerSettings.productName);
if (content != newcontent)
{
File.WriteAllText(actualFilePath, newcontent);
AssetDatabase.Refresh();
}
}
}
And this is the contents of my file c:\Program Files\Unity\Editor\Data\Resources\ScriptTemplates\81-C# Script-NewBehaviourScript.cs.txt
using UnityEngine;
namespace #PROJECTNAME#
{
public class #SCRIPTNAME# : MonoBehaviour
{
// Start is called before the first frame update
void Start()
{
}
// Update is called once per frame
void Update()
{
}
}
}

Here is my solution, in my case Unity added the root namespace right before OnWillCreateAsset(), so I had to replace the root namespace in the script with the one I want.
Here is the code
public class AddNameSpace : UnityEditor.AssetModificationProcessor
{
public static void OnWillCreateAsset(string path)
{
var rootNamespace =
string.IsNullOrWhiteSpace(EditorSettings.projectGenerationRootNamespace) ?
string.Empty : $"{EditorSettings.projectGenerationRootNamespace}";
path = path.Replace(".meta", "");
int index = path.LastIndexOf(".");
if (index < 0)
return;
string file = path.Substring(index);
if (file != ".cs" && file != ".js" && file != ".boo")
return;
string formattedNamespace = GetNamespace(path, rootNamespace);
file = System.IO.File.ReadAllText(path);
if (file.Contains(formattedNamespace))
return;
file = file.Replace(rootNamespace, formattedNamespace);
System.IO.File.WriteAllText(path, file);
AssetDatabase.Refresh();
}
private static string GetNamespace(string filePath, string rootNamespace)
{
filePath = filePath.Replace("Assets/Scripts/", "/")
.Replace('/', '.')
.Replace(' '.ToString(), string.Empty);
var splitPath = filePath.Split('.');
string pathWithoutFileName = string.Empty;
for (int i = 1; i < splitPath.Length - 2; i++)
{
if (i == splitPath.Length - 3)
{
pathWithoutFileName += splitPath[i];
}
else
{
pathWithoutFileName += splitPath[i] + '.';
}
}
return $"{rootNamespace}.{pathWithoutFileName}";
}
}

Archestra Client Control Importing dll file

So I have Wonderware Archestra IDE 4.1. Basically latest and greatest that is 2015 on a server
I have a C# class library called WordControls that is created in Visual Studio 2015 on my laptop. When I build it, the release is a dll file of the same name.
I copy and paste the dll file into the server's Documents folder and it should be as simple as moving the mouse to the top left and drilling down to this:
Galaxy -> Import -> Client Control
And from there I select my dll file that I created and click Ok. Then click Ok again on the default. And finally it goes through the import process. Except that instead of importing the file in, I get something slightly different:
"Processing file WordControls.dll....
Imported total of 0 object(s) from 1 file(s)"
It fails to import the dll and I don't know why. I've done it before in my previous job on a 2014 Archestra and Visual Studio 2013 so I cannot seem to figure out what I've done wrong.
Has anyone had the experience in working with the client control aspect of Archestra IDE?
When I look at the SMC logger I get these two warnings:
Microsoft.Office.Interop.Word, Version=15.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c Dependant File does not exist.
Controls not found in C:\Users\vegeto18\Documents\WordControls.dll.
I’m not sure what to make of the first warning besides the fact that my program does use Microsoft.Office.Interop.Word to work with MS docs and that the server doesn’t have MS Office (the terminal servers that are deployed with Intouch view apps).
The second part I’m not exactly sure how to interpret since that is where the dll is located after I copy it from my laptop and paste it into that folder.
This would be my code:
using System;
using System.Windows.Forms;
using Microsoft.Office.Interop.Word;
using System.IO;
namespace WordControls
{
public partial class DocBrowser : Form
{
private System.Windows.Forms.WebBrowser webBrowser1;
delegate void ConvertDocumentDelegate(string fileName);
public DocBrowser()
{
InitializeComponent();
// Create the webBrowser control on the UserControl.
// This code was moved from the designer for cut and paste
// ease.
webBrowser1 = new System.Windows.Forms.WebBrowser();
webBrowser1.Dock = System.Windows.Forms.DockStyle.Fill;
webBrowser1.Location = new System.Drawing.Point(0, 0);
webBrowser1.MinimumSize = new System.Drawing.Size(20, 20);
webBrowser1.Name = "webBrowser1";
webBrowser1.Size = new System.Drawing.Size(532, 514);
webBrowser1.TabIndex = 0;
Controls.Add(webBrowser1);
// set up an event handler to delete our temp file when we're done with it.
webBrowser1.DocumentCompleted += webBrowser1_DocumentCompleted;
}
private void Form1_Load(object sender, EventArgs e)
{
var url = "http://qualityworkbench/ivscripts/qwbcgi.dll/docfetchraw?db=live&id=1090";
LoadDocument(url);
}
string tempFileName = null;
public void LoadDocument(string fileName)
{
// Call ConvertDocument asynchronously.
ConvertDocumentDelegate del = new ConvertDocumentDelegate(ConvertDocument);
// Call DocumentConversionComplete when the method has completed.
del.BeginInvoke(fileName, DocumentConversionComplete, null);
}
void ConvertDocument(string fileName)
{
object m = System.Reflection.Missing.Value;
object oldFileName = (object)fileName;
object readOnly = (object)false;
Microsoft.Office.Interop.Word.Application ac = null;
try
{
// First, create a new Microsoft.Office.Interop.Word.ApplicationClass.
ac = new Microsoft.Office.Interop.Word.Application();
// Now we open the document.
Document doc = ac.Documents.Open(ref oldFileName, ref m, ref readOnly,
ref m, ref m, ref m, ref m, ref m, ref m, ref m,
ref m, ref m, ref m, ref m, ref m, ref m);
// Create a temp file to save the HTML file to.
tempFileName = GetTempFile("html");
// Cast these items to object. The methods we're calling
// only take object types in their method parameters.
object newFileName = (object)tempFileName;
// We will be saving this file as HTML format.
object fileType = (object)WdSaveFormat.wdFormatHTML;
// Save the file.
doc.SaveAs(ref newFileName, ref fileType,
ref m, ref m, ref m, ref m, ref m, ref m, ref m,
ref m, ref m, ref m, ref m, ref m, ref m, ref m);
}
finally
{
// Make sure we close the application class.
if (ac != null)
ac.Quit(ref readOnly, ref m, ref m);
}
}
void DocumentConversionComplete(IAsyncResult result)
{
// navigate to our temp file.
webBrowser1.Navigate(tempFileName);
}
void webBrowser1_DocumentCompleted(object sender,
WebBrowserDocumentCompletedEventArgs e)
{
if (tempFileName != string.Empty)
{
// delete the temp file we created.
File.Delete(tempFileName);
// set the tempFileName to an empty string.
tempFileName = string.Empty;
}
}
string GetTempFile(string extension)
{
// Uses the Combine, GetTempPath, ChangeExtension,
// and GetRandomFile methods of Path to
// create a temp file of the extension we're looking for.
return Path.Combine(Path.GetTempPath(),
Path.ChangeExtension(Path.GetRandomFileName(), extension));
}
}
}

There was nothing wrong with my code, it was my project type. I wrote this on Visual Studio as a Window Forms Application. I was supposed to use Window Forms User Control. This ended up resolving my issue.

Cannot apply indexing with[] to an expression of type

I am creating an SSIS package and want to include a script which checks if a file exist before retrieving the file and saving that data to a table.
I have three separate variable that I have set up:
fileExistFlag Int32 0
fileName String check.txt
folderPath String C:\
My C# code looks like this, where I am checking:
public void Main()
{
// TODO: Add your code here
String fp = Dts.Variables["User::folderPath"].Value.ToString() + Dts.Variables["User::fileName"].Value.ToString();
if (File.Exists(fp))
{
Dts.Variables["User::fileExistFlag"].Value = 1;
}
MessageBox.Show(fp);
MessageBox.Show(Dts.Variables["User::fileExistFlag"].Value.ToString());
Dts.TaskResult = (int)ScriptResults.Success;
}
When I try to compile my script, I receive the following error:
Cannot apply indexing with [] to an expression of type 'Microsoft.SqlServer.Dts.Runtime.Variables for all four instances.
How can I solve the issue?
Updated code:
/*
Microsoft SQL Server Integration Services Script Task
Write scripts using Microsoft Visual C# 2008.
The ScriptMain is the entry point class of the script.
*/
using System;
using System.Data;
using Microsoft.SqlServer.Dts.Runtime;
using System.Windows.Forms;
using System.IO;
namespace ST_04f6fa3ba49a4ddeac3d3d7fc29f04f2.csproj
{
[System.AddIn.AddIn("ScriptMain", Version = "1.0", Publisher = "", Description = "")]
public partial class ScriptMain : Microsoft.SqlServer.Dts.Tasks.ScriptTask.VSTARTScriptObjectModelBase
{
#region VSTA generated code
enum ScriptResults
{
Success = Microsoft.SqlServer.Dts.Runtime.DTSExecResult.Success,
Failure = Microsoft.SqlServer.Dts.Runtime.DTSExecResult.Failure
};
#endregion
/*
The execution engine calls this method when the task executes.
To access the object model, use the Dts property. Connections, variables, events,
and logging features are available as members of the Dts property as shown in the following examples.
To reference a variable, call Dts.Variables["MyCaseSensitiveVariableName"].Value;
To post a log entry, call Dts.Log("This is my log text", 999, null);
To fire an event, call Dts.Events.FireInformation(99, "test", "hit the help message", "", 0, true);
To use the connections collection use something like the following:
ConnectionManager cm = Dts.Connections.Add("OLEDB");
cm.ConnectionString = "Data Source=localhost;Initial Catalog=AdventureWorks;Provider=SQLNCLI10;Integrated Security=SSPI;Auto Translate=False;";
Before returning from this method, set the value of Dts.TaskResult to indicate success or failure.
To open Help, press F1.
*/
public void Main()
{
// TODO: Add your code here
String fp = Dts.Variables.Get("User::folderPath").Value.ToString() + Dts.Variables.Get("User::fileName").Value.ToString();
if (File.Exists(fp))
{
Dts.Variables.Get("User::fileExistFlag").Value = 1;
}
MessageBox.Show(fp);
MessageBox.Show(Dts.Variables.Get("User::fileExistFlag").Value.ToString());
Dts.TaskResult = (int)ScriptResults.Success;
}
}
public static Microsoft.SqlServer.Dts.Runtime.Variable Get(
this Microsoft.SqlServer.Dts.Runtime.Variables variables, string name)
{
foreach(Microsoft.SqlServer.Dts.Runtime.Variable item in variables)
{
if(item.Name == name) return item;
}
return null;
}
}

This is a known BUG in SQL Server BIDS 2005/2008 after installing side by side a later version of SSIS. For example if you are developing a SSIS 2008 package and then install SSIS 2012.
A workaround is to move the file "Microsoft.SQLServer.ManagedDTS.dll" located in the path:
"C:\Program Files (x86)\Microsoft SQL Server\110\SDK\Assemblies" to a backup folder, then the bids take the reference from the path "C:\Windows\assembly\GAC_MSIL\Microsoft.SqlServer.ManagedDTS\10.0.0.0__89845dcd8080cc91\"
But it doesn't seem to work for all the cases reported.
Source:
https://connect.microsoft.com/SQLServer/feedback/details/744390/ssis-any-pre-2012-error-cannot-apply-indexing-with-to-an-expression-of-type-microsoft-sqlserver-dts-runtime-variables
http://support.microsoft.com/kb/938608/en-us

Oddly, this indexer does seem to exist. If it isn't working, though, you might be able to use an extension method:
public static class MyExtensionMethods
{
public static Microsoft.SqlServer.Dts.Runtime.Variable Get(
this Microsoft.SqlServer.Dts.Runtime.Variables variables, string name)
{
foreach(Microsoft.SqlServer.Dts.Runtime.Variable item in variables)
{
if(item.Name == name) return item;
}
return null;
}
}
and use:
... Dts.Variables.Get("User::folderPath").Value ...
instead.

Use Browse in the add references window and look for this dll: C:\Program Files (x86)\Microsoft SQL Server\100\SDK\Assemblies\Microsoft.SQLServer.ManagedDTS.dll

How can I open AutoCAD 2015 through the .NET API

I've been browsing for a good hour and have yet to find something that would help with this. I'm working on opening AutoCAD from the .NET API in VS2013 using C#, but for some reason, I can never get AutoCAD to actually launch. I'm using the following code:
using System;
using System.Runtime.InteropServices;
using Autodesk.AutoCAD.Interop;
using Autodesk.AutoCAD.Runtime;
using Autodesk.AutoCAD.ApplicationServices;
namespace IOAutoCADHandler
{
public static class ACADDocumentManagement
{
[CommandMethod("ConnectToAcad")]
public static void ConnectToAcad()
{
AcadApplication acAppComObj = null;
// no version number so it will run with any version
const string strProgId = "AutoCAD.Application";
// Get a running instance of AutoCAD
try
{
acAppComObj = (AcadApplication)Marshal.GetActiveObject(strProgId);
}
catch // An error occurs if no instance is running
{
try
{
// Create a new instance of AutoCAD
acAppComObj = (AcadApplication)Activator.CreateInstance(Type.GetTypeFromProgID(strProgId), true);
}
catch //// STOPS HERE
{
// If an instance of AutoCAD is not created then message and exit
// NOTE: always shows this box and never opens AutoCAD
System.Windows.Forms.MessageBox.Show("Instance of 'AutoCAD.Application'" +
" could not be created.");
return;
}
}
// Display the application and return the name and version
acAppComObj.Visible = true;
System.Windows.Forms.MessageBox.Show("Now running " + acAppComObj.Name +
" version " + acAppComObj.Version);
// Get the active document
AcadDocument acDocComObj;
acDocComObj = acAppComObj.ActiveDocument;
// Optionally, load your assembly and start your command or if your assembly
// is demandloaded, simply start the command of your in-process assembly.
acDocComObj.SendCommand("(command " + (char)34 + "NETLOAD" + (char)34 + " " +
(char)34 + #"C:\Users\Administrator\Documents\All Code\main-libraries\IOAutoCADHandler\bin\Debug\IOAutoCADHandler.dll" + (char)34 + ") ");
acDocComObj.SendCommand("DRAWCOMPONENT");
}
}
Unfortunately, it always stops at the nested catch statement and always displays the popup box without opening AutoCAD. Any suggestions on how to at least make AutoCAD open for me?
EDIT: Error message

The issue is you're coding (correctly) to the AutoCAD interop interface. I recommend against that (due to potential version changes).
The other issue is that the documentation for AutoCAD plugins using the newer .net api is for plugins when AutoCAD is already running.
Final issue could be that the program Id of AutCAD is a mystery. I have resorted to making that a configurable setting, but default to "AutoCAD.Application", which will take the currently registered AutoCAD.Application on the production machine. If there are multiple versions installed on the machine and you want to be specific, then you could append the version number (which you'll need to research) to the ProgID like: "AutoCAD.Application.19", or "AutoCAD.Application.20" for 2015.
For the first issue, one technique is to use dynamics for the autoCad objects, particularly for creating instances. I have used the ObjectARX api for creating my application in a dummy project, and then switching to dynamics when I'm happy with the properties and method names.
In a standalone .Net application that starts AutoCAD you could use something like:
// I comment these out in production
//using Autodesk.AutoCAD.Interop;
//using Autodesk.AutoCAD.Interop.Common;
//...
//private static AcadApplication _application;
private static dynamic _application;
static string _autocadClassId = "AutoCAD.Application";
private static void GetAutoCAD()
{
_application = Marshal.GetActiveObject(_autocadClassId);
}
private static void StartAutoCad()
{
var t = Type.GetTypeFromProgID(_autocadClassId, true);
// Create a new instance Autocad.
var obj = Activator.CreateInstance(t, true);
// No need for casting with dynamics
_application = obj;
}
public static void EnsureAutoCadIsRunning(string classId)
{
if (!string.IsNullOrEmpty(classId) && classId != _autocadClassId)
_autocadClassId = classId;
Log.Activity("Loading Autocad: {0}", _autocadClassId);
if (_application == null)
{
try
{
GetAutoCAD();
}
catch (COMException ex)
{
try
{
StartAutoCad();
}
catch (Exception e2x)
{
Log.Error(e2x);
ThrowComException(ex);
}
}
catch (Exception ex)
{
ThrowComException(ex);
}
}
}

When there are several versions of AutoCAD installed on a computer, creating an instance with the ProgID "AutoCAD.Application" will run the latest version started on this computer by the current user. If the version of the Interop assemblies used does not match the version that is starting, you'll get a System.InvalidCastException with an HRESULT 0x80004002 (E_NOINTERFACE).
In your specific case, the {070AA05D-DFC1-4E64-8379-432269B48B07} IID in your error message is the GUID for the AcadApplicationinterface in R19 64-bit (AutoCAD 2013 & 2014). So there is an AutoCAD 2013 or 2014 that is starting, and you cannot cast this COM object to a 2015 type because 2015 is R20 (not binary compatible).
To avoid that, you can add a specific version to your ProgID (like "AutoCAD.Application.20" for AutoCAD 2015 (R20.0) to 2016 (R20.1)) to start the version matching your Interop assemblies or you can use late binding (eg. remove your references to Autodesk.AutoCAD.Interop* and use the dynamic keyword instead of the AutoCAD types).
In the last case, you will lost autocompletion, but your program will work with all the versions of AutoCAD.
Check also 32-bit vs 64-bit because TypeLib/Interop assemblies are not the same.

I open the application in a much straight-forward way. First, be sure to reference the correct type library. The one I am using is AutoCAD 2014 Type Library, located at:
c:\program files\common files\autodesk shared\acax19enu.tlb
To initialize the application:
using AutoCAD;
namespace test
{
class Program
{
static void Main(string[] args)
{
AutoCAD.AcadApplication app;
app = new AcadApplication();
app.Visible = true;
Console.Read();
}
}
}

Try this:
"sourcefile" is the original file
"newfile" is the new file
[CommandMethod("ModifyAndSaveas", CommandFlags.Redraw | CommandFlags.Session)]
public void ModifyAndSaveAs()
{
Document acDoc = Application.DocumentManager.Open(sourcefile);
Database acDB = acDoc.Database;
Transaction AcTran = acDoc.Database.TransactionManager.StartTransaction();
using (DocumentLock acLckDoc = acDoc.LockDocument())
{
using (AcTran)
{
BlockTable acBLT = (BlockTable)AcTran.GetObject(acDB.BlockTableId, OpenMode.ForRead);
BlockTableRecord acBLTR = (BlockTableRecord)AcTran.GetObject(acBLT[BlockTableRecord.ModelSpace], OpenMode.ForRead);
var editor = acDoc.Editor;
var SelectionSet = editor.SelectAll().Value;
foreach (ObjectId id in SelectionSet.GetObjectIds())
{
Entity ent = AcTran.GetObject(id, OpenMode.ForRead) as Entity;
//modify entities
}
AcTran.Commit();
}
}
acDB.SaveAs(newfile, DwgVersion.AC1021);
}

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Diagnostics;
using System.Runtime.InteropServices;
namespace Tekkit
{
class Program
{
static void Main(string[] args)
{
//make sure to add last 2 using statements
ProcessStartInfo start = new ProcessStartInfo("calc.exe");
Process.Start(start);//starts the process
}
}
}