Is there a file size limit when sharing files?
I don't think this problem is caused by the size of the file, but just one of those random hiccups that happens with AFP sometimes =/

Try using AirDrop if your on 10.7 Lion or higher. Even if your mac doesn't support AirDrop, there is a hidden command to allow for AirDrop to work over the local network (Ethernet or WiFi). See the link below.

http://hints.macworld.com/article.php?story=20110913213649565