File.Move Does Not Work – File Already Exists

What you need is:

if (!File.Exists(@"c:\test\Test\SomeFile.txt")) {
    File.Move(@"c:\test\SomeFile.txt", @"c:\test\Test\SomeFile.txt");
}

or

if (File.Exists(@"c:\test\Test\SomeFile.txt")) {
    File.Delete(@"c:\test\Test\SomeFile.txt");
}
File.Move(@"c:\test\SomeFile.txt", @"c:\test\Test\SomeFile.txt");

This will either:

• If the file doesn’t exist at the destination location, successfully move the file, or;
• If the file does exist at the destination location, delete it, then move the file.

Edit: I should clarify my answer, even though it’s the most upvoted!
The second parameter of File.Move should be the destination file – not a folder. You are specifying the second parameter as the destination folder, not the destination filename – which is what File.Move requires.
So, your second parameter should be c:\test\Test\SomeFile.txt.