Argh! Nero's busted my MKVs!

[Evil Andy]

Over the course of several months I've been slowly backing up my Martian Successor Nadesico DVDs to Matroska files each containing one XVid stream, two HE-AAC streams and one SSA stream. Each of these worked perfectly until I used Nero to turn them into an NRG file (no errors reported) and then used Nero again to burn them to a DVD (no errors reported and verifier came up no errors).

0 errors all round so I deleted the files to free up the 4 or so gigs. A couple of days later I tried to watch one of the episodes to have both MPC and TCMP say they couldn't render the file. A quick inspection with mkvinfo reports that no EBML header could be found.

Is there anything I can do? Or am I going to have to spend another couple of months redoing ALL the episodes again.

I have successfully backed up DVDs to matroska format several times and successfully then put them on DVD with ImgTool Classic and DVDDecrypter. The only thing I've done different this time is use Nero.

[bond]

try remuxing with mkvmerge?

[jcsston]

@bond: mkvinfo reported no ebml header found so mkvmerge wouldn't be any different.

@Evil Andy: I've guessing that the DVD disc may have went bad, I've burn numerous CD and DVD with Matroska files and haven't had any problems with Nero breaking the files.
You could try running the Nero Tool CD Speed and the Extra->ScanDisc, Surface Scan to see if there are any detectable ECC errors on the disc.

[Evil Andy]

No luck with CD-DVD Speed. I've now tracked the problem down to the disc image.

I mounted the NRG image with Daemon Tools and then tried copying the episodes back to the hard drive. Half way through copying Ep01 I suddenly get an error message that 'The parameter is incorrect' or some such, and none of the other files will copy at all, giving the same error message. I've also found that the first half of Ep01 IS viewable with MPC.

So what seems to have happened is that Nero has written out the image's FAT (or whatever's the equivalent), written half of episode 1 then an error's crept in making the rest of the image garbage. It would appear that Nero has failed to realise it's screwed up totally and utterly. Which I guess means it's all unrecoverable.

I'll have a go running XP's Error-Checking on the hard disk in the totally unlikely hope it'll find something it can fix. Other than that I'll just have a little sob over the hours of subtitle editing I'll have to do all over again.

[Evil Andy]

Nope, no good. Guess it's lost.

[iapir]

Maybe it's just a bad media that you used ?

[Atamido]

No, it looks like he said that the original image file on his hard drive is corrupt. Apparently Nero screwed up making an image file on the hard drive before he ever tried to burn the image to some media. That is on serious screwup from Nero.

[Evil Andy]

Correct. My initial thought was of course that it was a bad burn despite the lack of errors reported by Nero but mounting the original image with Daemon Tools showed all but the first half of the first file to be garbage.

I should probably say that this is the first time Nero 6 has let me down and I've been using it quite happily since it was released (Nero 5 on the other hand... :p ). I'm especially impressed with the AAC encoder and I'm looking forward to trying out the AVC encoder when I get the chance.

[iapir]

For what you're doing, you'd better save your images using mksisofs rather than Nero. It works fine, makes compliant ISO files and can be used on all OSes.