I've had a tough week with my computer, I started getting crashes first in Firefox, then in other programs, then out of the blue with no warning when the machine was just sitting there at the desktop. I'd download files and try to open them, and windows would say they were corrupt. I've been using Acronis, and I'd try to verify the integrity of backup archives (on other hard drives) and Acronis would say those were corrupt, too - even ones I know I tried and verified at the time I made them. I'd run chkdsk and it would show errors, I'd run it at boot with /F to fix them, Windows would declare the disk clean and there would be more errors shortly afterwards.  I decided the main disk must be toast. I just bought the machine new from Lenovo in August (off their outlet page and for a song), called them and they overnighted me a new hard disk and a set of recovery CDs, bless their hearts. After more rigamorole (I had added a second hard disk and more memory to the machine, and it turns out I couldn't restore it until not only those parts but every peripheral including printers and sound was disconnected) I got it going again.  I'm almost convinced it might be stable. I've reinstalled Acronis and it declared an image I had from 10 days ago on an external disk verifies OK, so I should be able to get back that close, anyway (haven't restored it yet).

But I had a problem when I re-attached the second hard drive. It had been formatted into four partitions, I know the first one was FAT-32 and pretty small, the other three were NTFS.  They were filled with non-critical data - music files and the like. But at one point in the last couple of days I did get what I thought might be an OK Acronis image on there.  When I reattached the drive and rebooted the machine, it automatically wanted to do a chkdsk in it (which I foolishly let continue) and it appears to have hosed the partition table - now the disk shows only as Disk E: (the original FAT-32 portion). I disconnected it right away and I haven't lost anything critical if it's really messed up, but wonder what software might be good to non-destructively examine it to see if I can save anything. Any suggestions?

Many, many thanks, that did indeed do the trick.  The Acronis image I saved in the midst of my troubles is there, reported as corrupted, but I've been able to get a couple of files more recent than the complete image I had off of it successfully. I may get out of all of this headache relatively intact.

And just as a BTW, I've pretty much determined now that all of my problems stemmed not from a bad disk at all, but from a bad memory stick. And not even the original stick Lenovo shipped with the system, but an OCZ one I added later.  I'm going to have to go to them with my hat in hand to apologize tomorrow, but I've had enough for today.