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Registry Key Mapping

I am building an application in which I need to be able to gather information from the user's local Registry, and then utilize that to perform various tasks. I know where the certain registry key is located, but I can't seem to figure out how to properly extract the data. Here is the one I am trying to extract:
My ideal event would happen as follows: the utility searches for the registry value, determines it and stores it (in a var or something), then a button is displayed to the user to proceed to the next screen (I'm using WinForms). I have already set the button as "invisible" beforehand. See the attached code.
using (RegistryKey key = Registry.LocalMachine.OpenSubKey("HKEY_LOCAL_MACHINE\Software\Wow6432Node\DovetailGames\FSX\10.0"))
{
if (key != null)
{
Object o = key.GetValue("Install_Path");
if (o != null)
{
sc3op2.Visible = true; //Button is "sc3op2"
}
}
}
I guess my main problem is the formatting of the code to extract these values. Any help would be appreciated. Thanks.

Your answer might be here. Apparently, it has something to do with the virtualization of the application settings for 32 and 64-bit platforms. See the updated section If it returns null, set your build architecture to Any CPU. On my 64-bit platform, I am getting null when built using x86 or Any CPU build configuration. But it is returning the value when built using x64.
const string keyName = #"Software\Wow6432Node\DovetailGames\FSX";
var o = Registry.LocalMachine.OpenSubKey(keyName, false);
var value = o?.GetValue("Install_Path", "-");
Console.WriteLine(value);

First you need to remove HKEY_LOCAL_MACHINE.
You need to use # before the string.
take a look Screenshot
using (RegistryKey key = Registry.LocalMachine.OpenSubKey(#"SOFTWARE\Apple Inc.\Apple Application Support"))
{
if (key != null)
{
Object o = key.GetValue("Installdir");
if (o != null)
{
// do something
}
}
}

Find and Read registry key within CLR

I need to check the availability and also read some registry key by CLR(C#), registry keys already written by another application.
As a sample:
public bool IsKeyAvailable(string KeyID)
{
string keyToRead = #"Software\myRoot\myApp\" + KeyID;
using (RegistryKey regKey = Registry.CurrentUser.OpenSubKey(keyToRead, RegistryKeyPermissionCheck.ReadSubTree))
{
if (regKey == null)
return false;
return true;
}
}
Checking & reading code are working fine outside of the CLR, but within the CLR the same code doesn't working, Already signed the CLR and assembly created WITH PERMISSION_SET = UNSAFE.
What could be missed for this scenario to find and read my registry keys by CLR?

Use this code :
Registry.LocalMachine.OpenSubKey("SOFTWARE", true);
RegistryKey masterKey = Registry.LocalMachine.CreateSubKey("SOFTWARE\yourapp\yourkey");
string value = "";
if (masterKey != null)
{
value = masterKey.GetValue("yourvalue").ToString();
}
masterKey.Close();

Access remote registry key with C# in .Net MVC2

I'm using the following code
private static string GetLogonFromMachine(string machine)
{
//1. To read the registry key that stores this value.
//HKEY_Local_Machine\Software\Microsoft\Windows NT\CurrentVersion\WinLogon\DefaultUserName
var rHive = RegistryKey.OpenRemoteBaseKey(RegistryHive.LocalMachine, machine);
var rKey = rHive.OpenSubKey(#"Software\Microsoft\Windows NT\CurrentVersion\WinLogon");
var rItem = rKey.GetValue("DefaultUserName");
return rItem.ToString();
}
and I've confirmed that my user has access, the MVC site is using integrated authentication and that the listed REG_SZ "DefaultUserName" has a value on the machine targetted but rItem doesn't grab a value.
I guess I'm doing something silly and I'd love to know what!

I was indeed being silly. I wasn't sorting the list of machine names before use and so I was looking at the registry of the wrong machine. The machine that was actually in focus was correctly returning "".
I've ended up with
private static string GetLogonFromMachine(string machine)
{
//1. To read the registry key that stores this value.
//HKEY_Local_Machine\Software\Microsoft\Windows NT\CurrentVersion\WinLogon\DefaultUserName
RegistryKey rHive;
try
{
rHive = RegistryKey.OpenRemoteBaseKey(RegistryHive.LocalMachine, machine);
}
catch (IOException)
{
return "offline";
}
var rKey = rHive.OpenSubKey("Software\\Microsoft\\Windows NT\\CurrentVersion\\WinLogon\\");
if (rKey == null)
{
return "No Logon Found";
}
var rItem = rKey.GetValue("DefaultUserName");
return rItem==null ? "No Logon Found" : rItem.ToString();
}

Get a list of installed programs with application icons

I need to get a list of installed program on local machine with application icons. Below is the code snippet that am using to get the list of installed program and installed directory path.
/// <summary>
/// Gets a list of installed software and, if known, the software's install path.
/// </summary>
/// <returns></returns>
private string Getinstalledsoftware()
{
//Declare the string to hold the list:
string Software = null;
//The registry key:
string SoftwareKey = #"SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall";
using (RegistryKey rk = Registry.LocalMachine.OpenSubKey(SoftwareKey))
{
//Let's go through the registry keys and get the info we need:
foreach (string skName in rk.GetSubKeyNames())
{
using (RegistryKey sk = rk.OpenSubKey(skName))
{
try
{
//If the key has value, continue, if not, skip it:
if (!(sk.GetValue("DisplayName") == null))
{
//Is the install location known?
if (sk.GetValue("InstallLocation") == null)
Software += sk.GetValue("DisplayName") + " - Install path not known\n"; //Nope, not here.
else
Software += sk.GetValue("DisplayName") + " - " + sk.GetValue("InstallLocation") + "\n"; //Yes, here it is...
}
}
catch (Exception ex)
{
//No, that exception is not getting away... :P
}
}
}
}
return Software;
}
Now the issue is how i can get the installed application icon ?
Thanks in advance.

To determine if its an update, there will be a key called IsMinorUpgrade. This is present and set to a 1 for updates. If it's 0 or not present, then it's not an update.
To get an icon from an executable, use this code:
VB:
Public Function IconFromFilePath(filePath As String) As Icon
Dim result As Icon = Nothing
Try
result = Icon.ExtractAssociatedIcon(filePath)
Catch ''# swallow and return nothing. You could supply a default Icon here as well
End Try
Return result
End Function
C#:
public Icon IconFromFilePath(string filePath)
{
Icon result = null;
try {
result = Icon.ExtractAssociatedIcon(filePath);
} catch { }
return result;
}

To extract icon of installed windows application first we need to figure out the location of icon for the installed windows application. This information is stored in registry at following locations -
Key name - HEKY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall
Value - DisplayIcon
Key name - HKEY_CLASSES_ROOT\Installer\Products{productID}
Value - ProductIcon
For more detail and code to get application icons -
http://newapputil.blogspot.in/2015/06/extract-icons-of-installed-windows_17.html

How to search for specific value in Registry keys

How can I search for specific value in the registry keys?
For example I want to search for XXX in
HKEY_CLASSES_ROOT\Installer\Products
any code sample in C# will be appreciated,
thanks

In case you don't want to take a dependency on LogParser (as powerful as it is): I would take a look at the Microsoft.Win32.RegistryKey class (MSDN). Use OpenSubKey to open up HKEY_CLASSES_ROOT\Installer\Products, and then call GetSubKeyNames to, well, get the names of the subkeys.
Open up each of those in turn, call GetValue for the value you're interested in (ProductName, I guess) and compare the result to what you're looking for.

Help here...
Microsoft has a great (but not well known) tool for this - called LogParser
It uses a SQL engine to query all kind of text based data like the Registry,
the Filesystem, the eventlog, AD etc...
To be usable from C#, you need to build an Interop Assembly from the
Logparser.dll COM server using following (adjust LogParser.dll path)
command.
tlbimp "C:\Program Files\Log Parser 2.2\LogParser.dll"
/out:Interop.MSUtil.dll
Following is a small sample, that illustrates how to query for the Value
'VisualStudio' in the \HKLM\SOFTWARE\Microsoft tree.
using System;
using System.Runtime.InteropServices;
using LogQuery = Interop.MSUtil.LogQueryClass;
using RegistryInputFormat = Interop.MSUtil.COMRegistryInputContextClass;
using RegRecordSet = Interop.MSUtil.ILogRecordset;
class Program
{
public static void Main()
{
RegRecordSet rs = null;
try
{
LogQuery qry = new LogQuery();
RegistryInputFormat registryFormat = new RegistryInputFormat();
string query = #"SELECT Path from \HKLM\SOFTWARE\Microsoft where
Value='VisualStudio'";
rs = qry.Execute(query, registryFormat);
for(; !rs.atEnd(); rs.moveNext())
Console.WriteLine(rs.getRecord().toNativeString(","));
}
finally
{
rs.close();
}
}
}

This method will search a specified registry key for the first subkey that contains a specified value. If the key is found then the specified value is returned. Searchign is only one level deep. If you require deeper searching then I suggest modifying this code to make use of recursion. Searching is case-sensitive but again you can modify that if required.
private string SearchKey(string keyname, string data, string valueToFind, string returnValue)
{
RegistryKey uninstallKey = Registry.LocalMachine.OpenSubKey(keyname);
var programs = uninstallKey.GetSubKeyNames();
foreach (var program in programs)
{
RegistryKey subkey = uninstallKey.OpenSubKey(program);
if (string.Equals(valueToFind, subkey.GetValue(data, string.Empty).ToString(), StringComparison.CurrentCulture))
{
return subkey.GetValue(returnValue).ToString();
}
}
return string.Empty;
}
Example usage
// This code will find the version of Chrome (32 bit) installed
string version = this.SearchKey("SOFTWARE\\WOW6432Node\\Microsoft\\Windows\\CurrentVersion\\Uninstall", "DisplayName", "Google Chrome", "DisplayVersion");

#Caltor your solution gave me the answer I was looking for. I welcome improvements or a completely different solution that does not involve the registry. I am working with enterprise applications on Windows 10 with devices joined to Azure AD. I want/need to use Windows Hello for devices and for HoloLens 2 in a UWP app. My problem has been getting the AAD userPrincipal name from Windows 10. After a couple days searching and trying lots of code I searched the Windows Registry for my AAD account in the Current User key and found it. With some research it appears that this information is in a specific key. Because you can be joined to multiple directories there may be more than one entry. I was not trying to solve that issue, that is done with the AAD tenant Id. I just needed the AAD userPrincipal name.
My solution de-dups the return list so that I have a list of unique userPrincipal names. App users may have to select an account, this is tolerable for even HoloLens.
using Microsoft.Win32;
using System.Collections.Generic;
using System.Linq;
namespace WinReg
{
public class WinRegistryUserFind
{
// Windows 10 apparently places Office/Azure AAD in the registry at this location
// each login gets a unique key in the registry that ends with the aadrm.com and the values
// are held in a key named Identities and the value we want is the Email data item.
const string regKeyPath = "SOFTWARE\\Classes\\Local Settings\\Software\\Microsoft\\MSIPC";
const string matchOnEnd = "aadrm.com";
const string matchKey = "Identities";
const string matchData = "Email";
public static List<string> GetAADuserFromRegistry()
{
var usersFound = new List<string>();
RegistryKey regKey = Registry.CurrentUser.OpenSubKey(regKeyPath);
var programs = regKey.GetSubKeyNames();
foreach (var program in programs)
{
RegistryKey subkey = regKey.OpenSubKey(program);
if(subkey.Name.EndsWith(matchOnEnd))
{
var value = (subkey.OpenSubKey(matchKey) != null)? (string)subkey.OpenSubKey(matchKey).GetValue(matchData): string.Empty;
if (string.IsNullOrEmpty(value)) continue;
if((from user in usersFound where user == value select user).FirstOrDefault() == null)
usersFound.Add(value) ;
}
}
return usersFound;
}
}
}