I've done it before and it's not that hard. But, you'll need two partitions, and they'll need to be FAT32. PLEASE NOTE THAT AGAIN. Both partitions need to be FAT32!!!!
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If you go this route, you'll need a boot floppy to load CD Drivers. You can make one yourself @
http://www.nu2.nu (don't you just have laziness?)
Download the BFD pack, and the other stuff it tells you to, and run bfd cdrom i think it is. I'm assuming it's atapi....so you should not have to add any files. if it's scsi....have fun (but the directions are there for that too)
Actually.....with Bart's new wonderful tool, you can use this disk for both purposes that you need it for (repartitioning and copying from the cd). But you'll want to make sure you get a copy of win98's fdisk and include it on the cd (again, the web site tells you where to put the files).
So, if you've got an existing install of XP, and it takes up the current HD and you don't have a free partition, you're hosed (but not quite

)
With an existing install, since you're going to be starting over anyway:
1. Create a boot flopyy to load the cd drivers(see above) and add Fdisk.com, and format.com from a win98 computer to the appropriate directory
2. Add Smartdrv.exe (again, from a win98 machine) to the appropriate directory
3. Add xcopy32.exe and xcopy32.mod from a windows machine to the appropriate directory
PS...appropriate directory is to the location that bart specifies in his directions (you'll understand when you go to his site)
Anyway:
After you've backed up the files you need, just reboot to the disk you created in step one above
Run Fdisk. Create two partitions. Make sure to mark your install to partition as active. The second partition can be primary or logical (in extended partition). THe second partition I think can be about 700Megs.....don't need a lot of space.
Reboot again.
you will now have two partitions on your HD, C; and D: And, hopefully, loaded CD drivers.
Now, you have to format both partitions ( you can use format /u if you want, but it takes long time)
assuming your cd rom loaded to the e:\ place your xp cd rom in the cd tray. find the i386 Directory.
Bart's floopy disk creates a path variable on bootup, so all the files you copied to it are run from the ram drive, and you don't have to change to their directory to run them.......
but now you can run xcopy32 e:\<path to your cd rom i386>\*.* d:\wsour /e
xcopy32 will now ask you if this is a F-File or D Directory (press D)
Let it run.
After all that's said and done with reboot again with the floppy drive
This time, on the boot menu, just do a plain boot (don't load your cd rom drivers)
From the A prompt, type Smartdrv.exe
Now, switch to your D:\ drive and type d:\wsour\i386\winnt
if it says command not found, type :
d:\ <enter>
dir /s winnt.* <enter>
and see where it says it's at
then cd to that dir, and type winnt
this will copy all the files you need (make sure again, that C:\ is primary, and set to active or this won't work right)
It's a M$FT temp install.......to copy all the files you need to your C Drive.
the end of this process will reboot your computer (take the floppy out)...a.nd your setup should now be running off of HD.
PS...if this doesn't work, the most likely culprit is C:\ not being set active.
I've done this exactly a bajillion times and I KNOW it works. I typed the whole driections from memory. PM Me if you have any ?'s