desync in MP menu

[Czynszol]

Hi...God it's another error
Sry,if this bug/error/fail was posted,give me the link,thanks.
Yesterday,game simply crashed,and i need to restart my PC.
After that,i can't join to ANY mp game session,expect servers on mod.
In default mow i have "different files may cause desync" or something.I think guys-you know how it goes.Please,if someone had that problem and repaired it,tell it to me
Greetings.