Can't join or create groups

If I try to invite somebody or if he invites me to join a group, I get disconnected from the game and after the game has automatically closed the game crashes...
How can I solve this problem without downloading all the full client again?
I've tried to reapir the client but the problem remains. My girlfriend has the same version of my client (last official version by NCSoft) but she doesn't have any problem.

 

u cant solve it , its a server bug , the staff is working ro fix it but its not so easy , so we have to have some patience ^^
try not to group many times because urr char might remain stuck >.<

 

thank you very much for the answer daax

 

no problem ^^

 

I can't group either...makes me sad

 

I say leave it broke.
Barely anyone runs instances so maybe it'll help detour zergs ._.