When Stronghold is not running please do the following -

Locate the Stronghold.exe and type - File Explorer into the Search bar and then copy and paste this line into the File Explorer search bar -
C:\Program Files (x86)\Steam\steamapps\common\Stronghold

Right click on the Stronghold.exe file and select Properties, click on Compatibility -

1. 'Run this program as an administrator'

If this doesn't allow the game to run, please try the following -

2. 'Run this program in compatibility mode for' - 'Windows XP SP3'
Tick 'Override high DPI scaling behaviour'

If after running the game a 0x22 error message appears. Please enable Directplay.

Directplay can be accessed via Programs and Features. Select 'Turn Windows features on or off', Locate 'Legacy Components' and tick Directplay and click on OK.
Windows will install the necessary components.

Run the Stronghold.