I used to own 7th Guest. Isn't it a DOS game?
I'm just shooting in the dark, I no longer possess this game so I can't be of 'much' help, but if it is a dos game, have you tried using DosBox to run it?
If its not a dos game, have you tried setting the Compatibility to Windows 98/95? <right click on shortcut icon, click properties, then click the compatibility tab, in that window select windows 98 or 95 from the drop down list, click apply, then ok> If your icon does not have a compatibility tab in the properties menu, you can force one to create by deleting the desktop icon, and then making a new one by right clicking and selecting New > shortcut, then pointing to the .exe for the game. When the new icon is created it WILL have a compatibility tab.
Again, maybe this is helpful, maybe not. sorry I couldn't help more.
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