[Tony M]

I believe that is the problem. If you miss a sim or two and then update the file if the length of time that has simmed is greater than the "save messages for x days" field then the messages.dat file knows there is a message but there is no related message_xxxx.txt file to match up to it.

This is something that isn't an issue with the game as the option for setting the amount of text messages to be uploaded is a user option. Obviously setting this really high to deal with cases where people don't always download could lead to larger online league files