What? So you are telling me that NOD32 just happened to pick that exact file to show on the log file, for whatever reason, at the exact time I found that all my email was gone? Please explain exactly what you mean... If NOD32 is reporting that the file could NOT be opened it must be because at least it TRIED to open it. Sure, it did not succeed in OPENING the .msf file, but because of this action it must of corrupted the file, thus the file turning into a 2KB unusable file! I checked myself: At the time this occurred there were 2 objects that interacted with the .msf file from Thunderbird, one being me as I used Thunderbird normally, and the other being NOD32 scanning for viruses in the NOD32 program folder. I know I did not CTRL+ALL and then press the DELETE button. I made sure I didn't by checking the Trash folder and by looking at all my other folders for potentially moved messages. So If I did not delete these emails, and by chance I see a NOD32 log (within seconds after I realize what just happened) that tells me that NOD32 tried to scan the file but could not... This I am quite sure is what caused some catastrophic fault within the file or Thunderbird. Do I make myself understood?