This is really common sense, but I'll share so you all can benefit from my mistake. ;(8 Create a backup folder in your Ttools folder. After you do a lot of work on your Aircrafts.txt or Flightplans.txt, drop a copy of them in the backup folder. This way, you won't lose hours of work when you accidentally run the TDecompiler. :-mad

Doh! *:-*