After installing MySQL locally, I was getting an error trying to import a backup. The error just said "lost connection". The import worked fine until it got to one of the tables with a blob field like optionimage. The problem was the data was bigger than the configured packet size. To fix go to the WorkBench (this works in 5.2.35CE) and open the Options File. On the Networking tab change max_allowed_packet to something like 4096M. If that doesn't work try a higher number.