Open a folder using Process.Start

Have you made sure that the folder "c:\teste" exists? If it doesn't, explorer will open showing some default folder (in my case "C:\Users\[user name]\Documents").

Update

I have tried the following variations:

// opens the folder in explorer
Process.Start(@"c:\temp");
// opens the folder in explorer
Process.Start("explorer.exe", @"c:\temp");
// throws exception
Process.Start(@"c:\does_not_exist");
// opens explorer, showing some other folder)
Process.Start("explorer.exe", @"c:\does_not_exist");

If none of these (well, except the one that throws an exception) work on your computer, I don't think that the problem lies in the code, but in the environment. If that is the case, I would try one (or both) of the following:

• Open the Run dialog, enter "explorer.exe" and hit enter
• Open a command prompt, type "explorer.exe" and hit enter

Just for completeness, if all you want to do is to open a folder, use this:

System.Diagnostics.Process.Start(new System.Diagnostics.ProcessStartInfo() {
    FileName = "C:\\teste\\",
    UseShellExecute = true,
    Verb = "open"
});

Ensure FileName ends with Path.DirectorySeparatorChar to make it unambiguously point to a folder. (Thanks to @binki.)

This solution won't work for opening a folder and selecting an item, since there doesn't seem a verb for that.