I Have A BIG Problem!

[ACC92]

CK2 won't start. A box pops up saying my platform is invalid.

My game was working fine a few days ago, I have Windows 7 which IS a valid platform regardless of what Steam says. How can I fix this?

 

[Clown]

CKII was updated to a 64bit client. Since you're still running Windows 7, I'd wager that you also have the 32bit version? If so, your only options are to revert to an older version of the game or update your OS. I'd strongly urge you to do the latter. Windows 7 is outdated and Windows 10 costs next to nothing.

 

[ACC92]

CKII was updated to a 64bit client. Since you're still running Windows 7, I'd wager that you also have the 32bit version? If so, your only options are to revert to an older version of the game or update your OS. I'd strongly urge you to do the latter. Windows 7 is outdated and Windows 10 costs next to nothing.

I used version 2.8.3.4, I don't want the most recent version anyway but it still says invalid.

 

[Yxklyx]

I used version 2.8.3.4, I don't want the most recent version anyway but it still says invalid.

I have no issues running the game in Windows 7.

 

[Lord_Bean]

Try verifying the integrity of game files via Steam. It is possible some have become corrupted or something. If that doesn't work you could try a full clean install of the game.