Client Error 13_4

I have gotten this twice today already.

I was playing Complex GM with my AK-Knife when it happened. It was very close to the end of the match and I was just about to get ace. I went to use the knife while the bomb was ticking and the error "Client Error 13_4 (or 14_3 don't quite remember popped up). Might have something to do with knifing with the ak-knife in Gm.. This happened again about 30 minutes later in the same channel on a Metro map. I was the last round and the bomb was just about to blow up. I killed someone and went to knife and it appeared. Luckily it the game saved faster than the error unlike the last time. The first time I didn't think it would kick me, but it dc'ed me from the room 5 second later.. Strange error. Sorry I didn't get the SS..