Client redownloads everything after crash [Client]

I was playing a normal game then when i lost my connection. I tried to reconnect but it fails, so i close and reopen my client. But when i reopen my client, it starts downloading "interface" for 950 ish mb(?) I though it is a new patch at first, but my friend said he just logged on and his client doesnt patch. So i tried to relog and it still trying to redownload the client......

Is there anything i can do to fix this? I dont want to redownload 3gb with my 100kbps connection.. please help. Sorry for bad english. I hope i post this in the right section.

[Edit] I tried to "Repair" but nothing happened. Please tell me what information/logs i should provide.