I just copy paste from the DVDXCopy forum:
(by ireland, DVDXCopy Moderator, I hope I have his permission!)
\"What is a TDF file?
TDF stands for “Title Definition Format”. TDF files contain setup instructions that tell DVD X Copy XPRESS how back up a DVD movie. TDF files for DVD X Copy XPRESS are intended to be used only to fix incorrect titleset selections made by DVD X Copy XPRESS and DVD authoring problems inherent in some DVD movies.
How do I know if I need a TDF file?
A TDF file will not fix a failed backup. TDF files do not correct driver problems or bugs that may exist in the application. However, if you successfully create a backup but the backup has the incorrect titleset, audio language, video format, or subtitle on it, it is likely that a TDF file will fix the problem.
Where can I get TDF files?
If you think you need a TDF file, you can search for it on AfterDawn forum at
http://dvdxcopy.afterdawn.com/forum_view.cfm/76.
If you can not locate a TDF file you think you need, you can request one to be created at
http://dvdxcopy.afterdawn.com/forum_view.cfm/75.
If you make a request to have a TDF file created, please be sure to specify the exact movie title and the problem you are experiencing.\"
I hope this helps.
