How to detect whether Vista UAC is enabled

For those of us working in C#, in the Windows SDK there is a "UACDemo" application as a part of the "Cross Technology Samples". They find if the current user is an administrator using this method:

private bool IsAdministrator
{
    get
    {
        WindowsIdentity wi = WindowsIdentity.GetCurrent();
        WindowsPrincipal wp = new WindowsPrincipal(wi);

        return wp.IsInRole(WindowsBuiltInRole.Administrator);
    }
}

(Note: I refactored the original code to be a property, rather than an "if" statement)

As of 2017, an easy method to achieve this is the following:

import ctypes, sys

def is_admin():
    try:
        return ctypes.windll.shell32.IsUserAnAdmin()
    except:
        return False

if is_admin():
    # Code of your program here
else:
    # Re-run the program with admin rights
    ctypes.windll.shell32.ShellExecuteW(None, "runas", sys.executable, " ".join(sys.argv), None, 1)

If you are using Python 2.x, then you should replace the last line for:

ctypes.windll.shell32.ShellExecuteW(None, u"runas", unicode(sys.executable), unicode(" ".join(sys.argv)), None, 1)

Also note that if you converted you python script into an executable file (using tools like py2exe, cx_freeze, pyinstaller) then you should use sys.argv[1:] instead of sys.argv in the fourth parameter.

Some of the advantages here are:

• No external libraries required. It only uses ctypes and sys from standard library.
• Works on both Python 2 and Python 3.
• There is no need to modify the file resources nor creating a manifest file.
• If you don't add code below if/else statement, the code won't ever be executed twice.
• You can get the return value of the API call in the last line and take an action if it fails (code <= 32). Check possible return values here.
• You can change the display method of the spawned process modifying the sixth parameter.

Documentation for the underlying ShellExecute call is here.