Microsoft recently released an update for Windows Vista, Windows 7, Windows 8 and Windows 10 which prevents SafeDisc protected games, including Stronghold and Stronghold Crusader, from working correctly.
When running Stronghold or Stronghold Crusader either nothing will happen or you will receive the following message:
Access Denied: Please login with administrator privileges and try again.
Running the Windows Compatibility Wizard does not fix the issue.
To fix the issue please install the free HD version patch available from the following sites:
Stronghold Crusader Extreme