How about with Windows 98? It always seems to go wrong.

The last time it happened was when I took it in to a PC shop to have them put an additional drive in, and I told the man specifically to make sure I didn't lose my mail folders. No luck, all he could do was manage to save a few of the emails and a few of the addresses.

I know it can be done, and the fact it went wrong was because he screwed up. But the fact that someone who does it for a living screws it up like that confirms me in thinking it's not as straightforward as it should be, and it's not surprising it always goes wrong when I try to do it.