The new I0coin-qt client (from post# 1652) is working fine too. I just downloaded the entire block chain with no problems. Has anyone tried mining with the new client? I don't know if it had anything to do with the crash. It's more likely because of two different client versions being used for mining at the same time. Maybe the BIP16 & BIP30 patches kicked in before the 1 Oct 2012 deadline. If the new client works miners should be migrating to it to eliminate conflicts between the two.