July 9th, 2007
My “Backup and Restore” problem:
So, I decided to create a new backup with its new MediaID.bin and then use a hex viewer/editor to look at the contents of that file and then search for the same hex sequence in the backup catalog files. I found it, both in the global catalog file and the individual catalog files. I first tried to find the equivalent sequence in my old global catalog file, create the old MediaID.bin file, and then try to restore. For some reason, possibly an error on my part in identifying the correct sequence, it didn’t work. Then I did the same thing with one of the individual catalog files, using the ASCII sequence “Volume” as a marker. (That’s not actually the sequence, it’s in a 32-bit format and so there’s a 00 hex between each.) Comparing one of the new individual catalog files I had just created with an old one, and using the sequence from the new MediaID.bin as a guide, I identified what seemed to be the proper sequence from the old catalog file and recreated the old Media.Bin file—which was different from the one I had already tried. Then I tried a restore. It’s working! Yay! You have no idea how big of a relief this is for me. I was going to lost a lot of important data if I couldn’t figure this out. Unfortunately, however, I’m just guessing based upon file comparison and so there’s no programmatic way for me to automate this for other people’s use.
July 6th, 2007
In all my years of owning MS OSs (and I’ve actually bought them for the last ten years), two weeks ago I finally needed MS support for the first time. I bought Vista Ultimate for a bazillion dollars in January, so I figured I’d be able to get it. Not unreasonable, right? Nope. Only 90 days, and then you have to pay $60 for a single support call or email. I didn’t bother, support wouldn’t have been able to help me unless they were willing to contact the app development team.
I blame myself, though, for being stupid enough—for the first time, ever—to rely upon a Windows bundled application for something critical.
Here’s a tip: if you use “Backup and Restore” on Vista for file backup (not system backup), it writes a single file to the root of the backup media—like, say, your 500GB external hard drive—called MediaID.bin that, if it’s lost, your entire backup is unrecoverable. All the files are there in zip archives, which is fine for manual recovery for smaller ones. Anything large is split, within the zip files and across them. The pre-Vista version of these apps do this, too, but it was possible to simply concatenate the pieces back together. This doesn’t work with Vista. I suspect the idea for this ID file was for removable media like CD and DVD.
The actual backed-up files are in subdirectories and this ID file is the only thing placed in the root. I had also used the drive to manually copy files and directories I wanted to back up, and that’s how I ended up deleting this one, crucial file. It was stupid of me, but it’s also stupid design. And no one out there has a clue about how to recover these files. Short of getting obscure info from MS, I’m going to have to reverse engineer the structure of the catalog files, the ID file, and its generation. Then I’ll write a small utility to do the recovery and release it. I was going to do this when I thought the files could be concatenated—I thought, hey, this should be relatively easy and all these other folks with this problem will be so pleased to have the utility. Nope. Now the problem will be much more difficult to solve.
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