I've been searching this forum and I'm getting conflicting info on how IFOUpdate works. Here is my problem. I just finished encoding a DVD using DIF4U, Dc4U, Scenarist. The DVD only has a main menu and movie so its a fairly simple layout. 1) DIF4U creates a VIDEO_TS folder with the all original IFO and *_0.VOB files 2) Scenarist creates a Scenarist_OUTPUT folder with the re-authored VOB and IFO files When I use IFOUpdate, I point the "Original IFO Path" to the VIDEO_TS folder and point the "Authored IFO Path" to the Scenarist_OUTPUT folder. I set the following options in IFOUpdate: Transfer VTS_C_ADT Table Copy Color Table in Each OGC Autocorrect VTS Sectors (When Updating) Autoanalyze Original IFO (When Specified) When I hit the "UPDATE IFO" button, the IFO in the VIDEO_TS gets updated. I'm assuming it's the original IFO that should get updated by the IFO in Scenarist folder. Is this correct? I then copy all the Scenarist .VOB files over to the VIDEO_TS folder. I test it and the files play fine through WinDVD, IFOEdit and my APEX DVD player. But when I try it on 4 other DVD players, the DVD hangs and never gets to the main menu. It reads to the DVD then gives me an error on the DVD player display. Am I using IFOUpdate correctly here? Not sure if this is a problem with IFOUpdate, DIF4U, Dc4U, Scenarist or is it a problem with the burning app I am using that's causing some DVD players not to read my authored DVD properly. I'm using CopyToDVD as my burning app. I've used DVDShrink to do a 1:1 copy and burned and those played OK on all the DVD players I tried so I doubt it's a problem with CopyToDVD. Just curious if other people have seen this. Any help is appreciated since I've tried this method on 4 DVDs and I get the same results every time