Several points:
1.) Windows 7 does not fit on a CD, only a DVD.
2.) Drive letter (C:, D:, etc) depends on which OS you were running at the time. (Whichever you are running should always report itself as C
Thus, be sure you clarify what C: and D: are.
3.) If you tried to format C: as in the partition containing XP, that explains everything. Remember, format means 'delete all that is here' so by telling it to format C: you told it to delete Windows XP, all of your programs, all of your personal files, etc.
4.) In addition, the boot information for every OS installed is, by default, saved to the partition to which the first OS was installed. That means C: also included the boot information for Windows 7.
Thus, you're most likely in a situation where your backup is your only outlet as you prepare to reinstall Windows and all of your programs from scratch.
John
So, I installed the beta of win 7 on an old comp earlyer, just burned the image on a regular cd, so no bootability from cd.
Problem was my old win xp took up most room on c, so I had it installed on D:
So far so good, then I decide to format C:, that would make room for it and I can reinstall it there. Well, it seems that wasn't a very good idea, now comp doesn't seem to be able to use c:
It finds it and IDs it, but it can't format it, everything seems to be gone, it's just like an unformated disk.
Well, when I reboot my comp it won't boot, and I don't find a bootdisk for win7. It says I have to reinstall a .dll file because it's the wrong version, but that's probably because I tried my old XP bootdisk.
So, Any ideas?

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