On an a drive with XP it just takes all your DATA and puts it in the Windows.Old.
If it had been vista, it actually would have tried to keep the program up and running.
You do an upgrade option, which is close enough to a clean install. (I think of a clean install by formatting and wiping all the data off). You didn't do this, and this didn't happen. But a new OS was installed. I installed my upgrade windows 7 pro on my XP drive. At first it told me that it was going to put all my data into windows.old but then I formated the drive and it was all gone!
I have been looking forward to Windows 7 for quite some time. During that time I have been doing quite a bit of reading about all the upgrade options, installs, programs, etc. In my reading I kept finding people (and even Microsoft) saying that to upgrade from XP to Windows 7, a clean install must be done (in fact, inside, with the discs, there is a paper explaining to back up if you are upgrading from XP).
But I just finished my install, and I was putting my data back on (data that I painstackingly backed up, checking file for file, making sure everything was there {I know I could have done it with a program, much easier, but I just wanted to be safe}), and to my surprise my C drive was full. I go into it, and walah! Windows.old is there with all of my information from XP. It didn't delete a thing. I don't know if I should be worried or relieved.
I just thought it was odd. Did I install it wrong so it didn't do a clean install? Or is Microsoft just wrong about it deleting all your data? (I did use an upgrade version).

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