If you have a garena error, then go reinstall your garena programe; if you have a wc3 error, same thing go reinstall your wc3, so it will be fixed.
Anyway, it is not possible without any error message comes out, it must be you who clicked something like "close and don't send error", but I can give you a chance for now, just do what I said, if you have no clue where is the problem then do it both, and I hope it won't be happen again.
-rSK-SAMA can access this room from now on!