In one of my ongoing PBEM games I've now received two turns where I get the message "Failed to uncompress game data" when trying to open the turn. In the first instance, I was able to open it after trying again. Now, it keeps giving the same message over and over. Anyone have an idea what can cause/fix this?

Tough ****, do you happen to run a huge game? There were some reports of the error on the forums, but no solutions. Try reloading an older save.