So, it turns out I have completely wasted the last three days.

I kind of got sucked into installing windows 7 on my CAD box, as I need more memory now than XP can give me. I had a spare 80GB SSD, and foolishly thought I could use that to put a fresh install of Win7 onto, with the idea of making the machine dual bootable so I could switch from one to the other until I migrated everything across. There is a LOT of specialist software on the thing, it takes a good three days solid to install everything from scratch even if there are no problems encountered.

Add to that the complexity of all the graphics cards, device programmers, serial ports, instrumentation, etc, and it's a major pain in the arse getting everything working. Which is why I have been struggling with XP for so long rather than upgrading before

I have an extremely comprehensive backup system running, so in theory the risk to my data is minimal, but I didn't want any more downtime than I could avoid. I managed to restore a full system backup into a virtualbox VM, which worked surprisingly well, and the idea was to run windows 7 with a functional copy of the old XP machine in a virtualised form, with the actual xp installation as a backup.

It went quite well, at first...

After a couple of false starts I got 7 installed on the ssd, and spend two days installing all the software I could remember from the old machine, with all the other drives disconnected. When it was more or less ready with the major stuff installed, I only had one program that wouldn't work, and one piece of hardware (see previous post ). Then I made the mistake of plugging the old drives back in so I could copy my email settings, etc across. Bad mistake.

It worked as far as that was concerned, but when I rebooted the machine into XP to get some serial numbers everything started to fall down. The XP installation started complaining about unreadable or damaged files, ones I know for a fact were fine before Windows 7 started stirring the filesystem. When I ran chkdsk on all three original drives, ALL of them have bad files, directories, and MFT entries.

So I rebooted into windows 7 to see what it's version of chkdsk would say (and yes, I know enough not to run it in write mode on an XP disk). Except it won't boot. At all.

Blue screens instantly and resets the machine. I videoed the reboot process and was able to read the message, which was, in effect, "Something went wrong but we don't know what, rebooting". It goes into the repair manager, which will allow me to repair the OS, except that it can't see one.

At all.

Completely empty list. I tried in the end going into the command prompt, and drive C (the SSD at this point) is apparently corrupt and unreadable. Chkdsk is currently chewing on it, and is apparently rewriting every attribute of every file on the thing, and will probably destroy the FS completely.

It looks to me like microsoft have produced a pair of OSes that are so incompatible with each other that they fight to the death when on the same machine. Not at all helpful.

It's possible the SSD picked that moment to have a wobbly, but that doesn't explain why the XP installation bit it as well. SO it looks like I will have to reformat the whole bloody machine, and restore the original XP installation from the thankfully very complete and recent backup, and give up on windows 7. Annoying

pca