Windows 10 Press Windows Key + X, or right-click on the Start Menu button, then select 'System' in the menu that appears In the window that appears, click the 'System info' link on the right side Check for any entries named 'Domain' near the name of your computer Windows (All) Open Command Prompt Press Windows Key + R then enter cmd in the Run window that appears Search the Start Menu for Command Prompt Enter systeminfo | findstr /B "Domain" in the Command Prompt window, and press Enter If you are not joined to a domain, you should see 'Domain: WORKGROUP'. If you see something other than WORKGROUP, then you are likely joined to a domain