Well, first, the drive is physically 100% OK (as determined by WinDLG and SMART utilities).
Second, I've found no viruses.
Third, it seems the reason is a pre-SP1 WinXP (shame on me, I didn't know about the issue, I've learnt about it in this thread:
Maybe the pre-SP1 was on my friend's computer. When we copied files to/from my drive, the first partition got damaged. And of course the first thing I thought of was that I damaged the drive when handling it. But... it's strange that the computer crashed the second time, when I was working in WinXP SP1 from my disk D: Well, I created partitions D: and E: before installing SP1, so maybe this had some impact.
Anyway, it's more of theoretical interest now. What matters me now is how to restore partition E: in the MBR. PLEASE could anyone suggest a simple utility or procedure to do this? The partition (the file allocation table) looks mostly OK, the Stellar Phoenix demo finds it. But which utility can just write it to the MBR? As I understand, what Stellar Phoenix and many other utilities do is copy the restored files to another, healthy partition, but I don't have this option because there's just not enough free room. I just need to recover the partition.
Thanks in advance.