err use the search button
Most of us if not all of us play the English version.
But even if it had the same error in the English version, I've never come across it.
You could always google 'crossfire error code 7 help', I'm sure something about it will come up with other people having the same problem.
Or you could try re-installing Crossfire, that should work.
Also, try adding Crossfire to your 'Allow' list in Firewall, so it doesn't block any part of the program which may lead to the error.
Good luck!