System.UnauthorizedAccess Exception C# - c#

I currently have a compiled C# program but whenever I run it I get the Windows encountered a problem error.
This is from a System.UnauthorizedAccess error, how can I give access and remove this error without any need from the user side, since this program is being deployed to a lot of people and I don't want them having to make this fix manually.
Thanks

You can get the current user's application data folder using the environment variable APPDATA. Therefore, you can do something like:
string appdata = Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData)
string configFile = Path.Combine(appdata, configFile);
StreamWriter writer = new StreamWriter(configFile);
writer.WriteLine("my config data");
writer.Close();
You can also use this approach to get the temporary folder as well. You can even generate a random file name using the BCL functions. I think it's Path.GetTempFilename().

Does your application ask for Administrator's privileges at any time?

Related

How do i get access to C:\Program Files\ in c#

I want to save my Files in a more generic way than on Desktop.
So i want to create my own Subfolder in Programs Folder, which i can use to save my stuff.
But i get "System.UnauthorizedAccessException" if i try to create a File using File.AppendAllText(#"C:\Program Files\MySubfolder\MyFile.txt,someString);
I even disabled the Protection of the Folders manually.
My App is not yet compiled so i cant run it as administrator, can i?
How does every Program use this Folder but i cant?
Do i need to compile my App everytime i make a small change and want to test it?
I would really apreciate Help since im stuck with that multiple hours now
It is a very bad practice to try to write in Program Files. This folder as well as other sensitive folders are protected by the OS to prevent malicious code hide between your programs or to prevent unsavy users from messing on the installed programs.
If you want to write your private stuff on your disk you can use these folders
string folder = Environment.GetFolderPath(Environment.SpecialFolder.CommonApplicationData);
string myFolder = Path.Combine(folder, "MyReservedPath");
Directory.CreateDirectory(myFolder); // if exists does nothing
string myFile = Path.Combine(myFolder, "MyPrivateData.txt");
File.WriteAllText(myFile, dataToWriteOnDisk);
The CommonApplicationData resolves to C:\programdata and this place is usually used to store information needed by your program for any user that uses it.
If you want to store some data that your program produces then it is better to use the
Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments);
There are many other places available, just look at the Environment.SpecialFolder enum.
This code will give you a list of everything mapped to the actual folders in your system
foreach (Environment.SpecialFolder x in Enum.GetValues(typeof(Environment.SpecialFolder)))
Console.WriteLine($"{x} = {Environment.GetFolderPath(x)}");

OpenWrite UnauthorizedAccessException

I am working on a desktop application that internally creates a StringBuilder that errors get appended to and ultimately gets written to a txt file.
I get an exception that says 'Access to the path 'C:\Users\Me\Documents\test_dir\5_hundred_thousand_rows_Logs.txt' is denied.'
Below is the code that performs the creation of the .txt file. The exception catches on the File.OpenWrite(tempfile)) line
string tempfile="C:\\Users\\Me\\Documents\\test_dir\\5_hundred_thousand_rows_Logs.txt";
using (Stream fileStream = File.OpenWrite(tempfile))//exception here
{
string data = logFileContent.ToString();
Byte[] filecontent = new UTF8Encoding(true).GetBytes(data);
fileStream.Write(filecontent, 0, filecontent.Length);
}
Process.Start(tempfile);
I have double checked and the tempfile does indeed have the file extension and is not attempting to create a directory.
I've tried wrapping the using statement with the following to attempt to "grant" access but to no avail:
var permissionSet = new PermissionSet(PermissionState.None);
var writePermission = new FileIOPermission(FileIOPermissionAccess.AllAccess, Path.GetDirectoryName(tempfile));
writePermission.Demand();
permissionSet.AddPermission(writePermission);
FileAttributes attributes = File.GetAttributes(Path.GetDirectoryName(tempfile));
if (permissionSet.IsSubsetOf(AppDomain.CurrentDomain.PermissionSet))
{
// using statement
}
I am wanting this desktop application to be able to be handed to anyone and they be able to use this without having the user deal with folder permissions or something. Granted I'm really only expecting it to try to access MyDownloads, MyDocuments, directories on flash drives or other similar devices.
I would greatly appreciate any help provided.
EDIT:
It appears that this may be a Windows issue. The file is set to readonly in its properties (was not this way originally), and attempting to set the file as not readonly doesn't work as Windows apparently just resets it back to readonly. However if the file is not in a folder and is just sitting on the bare drive (such as a different drive eg: D:/5_hundred_thousand_rows_Logs.txt) it seems to work just fine. If there's a programmatic way to get around this I would appreciate it, but if this is a Windows issue this may require making this a different question.
According to the documentation the exception is thrown when you don't have the permissions, or the file is readonly.
To test if you don't have permissions, try and run your application as administrator. To verify the second case, right click the file in explorer, choose properties, and make sure it's not readonly.
Besides that string tempfile="C:\\Users\\Me\\Documents\\test_dir\\5_hundred_thousand_rows_Logs.txt"; is a weird path, because it's using the user me which definitelly doesn't exist on every machine. If you like to get the documents folder of the current user you can use: Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments); This will create the correct path for you.

call exe using Process without absolute path

I wrote a program need to call an external exe using
Process proc = Process.Start(filepath).
I specify the absolute path of the exe and it works fine. However, I need to use this program in different computers. Each time the exe has a different absolute path and I need to change the code for this part. I would like to know is there a way that I don't need to change the code? Thanks in advance!
You are asking the wrong question. Is not how to modify the API to work with your fixed requirements ("launch process w/o knowing the path", ignoring for a moment what huge security problem that is). The question you should ask is How can I modify my code to match the API I use?
Since starting a process works better if a full path is given (it also works if the executable name is in %PATH%, but that is a different topic), have you app figure out the correct path and then launch the process. There are countless ways to achieve this. Probably the safest option is to use an App.Setting that points to the path. At deployment the app is properly configured with the location of the required program. there are (many) more ways to do this, it will all depend on what you're actually trying to solve, more details would be needed.
If both exe-files are in the same folder, then
winforms:
var filepath = Path.Combine(Path.GetDirectoryName(Application.ExecutablePath), otherexename);
Process.Start(filepath);
wpf:
var filepath = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, otherexename)
Process.Start(filepath);
In a windows service, you can do the following to get the directory of the currently running assembly, then to generate the right path to your exe:
var directory = Path.GetDirectoryName(
new Uri(Assembly.GetExecutingAssembly().CodeBase).LocalPath);
var exeLocation = Path.Combine(directory,"myExe.exe");

Finding Install path of a program

I am new to C# and I have made a simple Windows Forms Application that basically updates the persons files for a game.
They have to manually move and delete certain folders just to change version every time. I have successfully accomplished this.
However before I start giving it out I really should improve it. I know I need to change the name of the processes and remove my descriptions ETC.
I have stumbled onto an error and instead of me taking a guess I think it is best to get an opinion from a more experienced person about how to do this.
I am going to use Inno Setup to make the installer for my application, this way I can be sure it will go into their program files 32 and 64 bit. So I know this will be in program files.
So now I am wondering if I have done this the correct way or not? I was using this format to find their program files:
string programFilesFolder = Environment.GetEnvironmentVariable("PROGRAMFILES(X86)") ?? Environment.GetFolderPath(Environment.SpecialFolder.ProgramFiles);
However, would this work on all windows systems(XP, Vista, Win7, Win8) and is it completely accurate? I was going to use the above, and then use this:
string PATCHSELECTOR = Path.Combine(programFiles, #"PATCH SELECTOR");
if (Directory.Exists(PATCHSELECTOR))
{
string GamereliteFolder = Path.Combine(programFiles, #"GAMERELITE~1");
if (Directory.Exists(GamereliteFolder))
And then I move the files using the string method. If the file exists it is deleted before I copy the file over from PATCH SELECTOR to GAMERELITE.
Also will windows XP support using the .exe with an assembly resource embedded which is making the program need to be ran as administrator? I previously was making the assembly work through UAC however that wouldnt always work if they have UAC off or if it is XP so I thought I would try the admin assembly instead.
Can anyone possibly give me some insight, ideas or links?
For executables (not sure for websites & web application) this returns the directory where the executable lives (it's actually the base path where the framework will probe for Assemblies to load, 99% of the the that's the same thing).
System.AppDomain.CurrentDomain.BaseDirectory
This method works for any executable located in a folder which is defined in the windows PATH variable:
private string LocateEXE(String fileName)
{
string path = Environment.GetEnvironmentVariable("path");
string[] folders = path.Split(';');
foreach (var folder in folders)
{
if (File.Exists(Path.Combine(folder, fileName)))
{
return Path.Combine(folder, fileName);
}
}
return String.Empty;
}
Usage:
string pathToEXE = LocateEXE("Example.exe");
Reference:
how to find the execution path of a installed software
How can I get another application's installation path programmatically?
Couple things:
Among the already stated answers, Assembly.GetExecutingAssembly().Location will also give you the full file path of the currently "executing" Assembly. (Alternatively, GetCurrentAssembly)
If I'm reading your question correctly, you're trying to find both your own location as well as another application's. I would highly recommend seeing if the other application has a registry key that specifies the exact location - it'll make your copy step WAY more stable.

Access to the path denied error in C#

I have read a similar post, but i just cant figure out the problem.
I have changed the windows permissions and changed routes.
When i try to save a file it throws me the exception:
Access to the path **** denied.
string route="D:\\";
FileStream fs = new FileStream(route, FileMode.Create); <--here is the problem
StreamWriter write = new StreamWriter(fs);
patient person = new patient();
patient.name = textBox1.Text;
patient.name2 = textBox2.Text;
You are trying to create a FileStream object for a directory (folder). Specify a file name (e.g. #"D:\test.txt") and the error will go away.
By the way, I would suggest that you use the StreamWriter constructor that takes an Encoding as its second parameter, because otherwise you might be in for an unpleasant surprise when trying to read the saved file later (using StreamReader).
Did you try specifing some file name?
eg:
string route="D:\\somefilename.txt";
tl;dr version: Make sure you are not trying to open a file marked in the file system as Read-Only in Read/Write mode.
I have come across this error in my travels trying to read in an XML file.
I have found that in some circumstances (detailed below) this error would be generated for a file even though the path and file name are correct.
File details:
The path and file name are valid, the file exists
Both the service account and the logged in user have Full Control permissions to the file and the full path
The file is marked as Read-Only
It is running on Windows Server 2008 R2
The path to the file was using local drive letters, not UNC path
When trying to read the file programmatically, the following behavior was observed while running the exact same code:
When running as the logged in user, the file is read with no error
When running as the service account, trying to read the file generates the Access Is Denied error with no details
In order to fix this, I had to change the method call from the default (Opening as RW) to opening the file as RO. Once I made that one change, it stopped throwing an error.
I had this issue for longer than I would like to admit.
I simply just needed to run VS as an administrator, rookie mistake on my part...
Hope this helps someone <3
If your problem persist with all those answers, try to change the file attribute to:
File.SetAttributes(yourfile, FileAttributes.Normal);
You do not have permissions to access the file.
Please be sure whether you can access the file in that drive.
string route= #"E:\Sample.text";
FileStream fs = new FileStream(route, FileMode.Create);
You have to provide the file name to create.
Please try this, now you can create.
TLDR : On my end, it had something to do with AVAST ! => Whitelist your application.
All of a sudden, I also got this UnauthorizedAccessException problem in the windows WPF program I'm writing. None of the solutions worked - except I couldn't figure out how to elevate my application to full privileges (not using VS) while at the same time, being already on the administrator account, I didn't feel the need to dig that deep in permission concerns.
The files are image files (jpg, psd, webp, etc.) I wasn't trying to open/write a directory, it has always been a valid path to a file, and I needed to write to the file, FileAccess.ReadWrite was inevitable. The files (and any of their parent directory) were not readonly (I even checked by code prior calling new FileStream(path, mode, access, share) via FileInfo.IsReadOnly) - so what happenned all of a sudden ???
Thinking about : I had an had drive crash, so I unpacked a backup of my solution code from another drive. In the meantime, I added codes in my application to PInvoke APIs to directly read hard drive sectors physical bytes as well as USB plug/unplug monitoring.
I started to get the Exception when I added those, but even though I temporarly removed the related codes from the application, I still got the UnauthorizedAccessException.
Then I remembered one thing I've done long ago, a painstaking similar issue where I wanted my application to communicate sensible data via Wifi, which was to add the executable among AVAST exceptions, and the assembly directory aswell (My app was already among the authorized apps through firewall)
Just did it for my application in AVAST settings, AND THE EXCEPTION IS GONE !!! Two whole days I'm lurking StackOverflow and the web to get moving on, FINALLY !
Details : I can't pinpoint exactly what AVAST didn't like in my application as the only changes I made :
Retrieved then launched the backup code - it worked like a charm, files (images) opens/write without problems (3 days ago)
Added USB detection (3 days ago - Just tested the code, didn't tried to open an image)
Added PInvoke physical drive direct read (2 days ago - FileStream, and the logic to define where/how to scan the damaged drive - Just tested the code, didn't tried to open an image)
Added image format detection starting from Jpg/Jfif.. 2 days ago, got the exception upon testing the code.
While searching for solutions, added an Image Gallery WPF UserControl to diplay pictures based on their signature and check which files gives the exception : almost all of them (some files opens/write okay - why ???)
Tried everything I've found on SO (since the last 2 days) until I opened AVAST settings and whitelist my application.
... now I can move on into adding a bunch of file signatures to retrieve as many datas as I could.
If this may help those who like me, aren't failing on the "I'm passing a directory path instead that of a file", yet, have no time to learn exactly why antiviruses think our own code is a malware.
Just Using the below worked for me on OSX.
var path = "TempForTest";

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