Well, I'm not an expert in that business, but I can give a suggeston.
First, reactOS can only read FAT16 and FAT32 partitions, wich means that if you want to share data with your winXP from ReactOS (and xp is on NTFS), u can't.
Second. I'll tell you how i did it.
First, I got a GParted CD and resized the partitions. My WinXPHome stayed in an ntfs partition. And i made up two other partitions, both FAT32.
The first one (FAT32) was for me to install reactOS, I installed it and did not wirte the MBR, i wrote to the diskette (it wasn't working till e ejected and inerted the diskette again).
After that, i booted my WinXP, to check if it all was OK.
So now i had two new partitions one wich allready had data, rebooted inserted the diskette (Notice that i defined my bios to start, first from the diskette then from de HD) and booted ReactOS. ReactOS recognised all of the HD's, but could only read two of them - It's HD and the other FAT32 HD.
So, I wn't back to Windows and gave name's to the HD's, to get oriented (something like - WindowsXP, ReactOS, FileSHare)
And I coppied some files to the FAT32 partitio wich didn't possess any OS. So I use that prtition to better file share and share applications, though i could of just been using ReactOS's partition, cause WindowsXP can write there, but to prevent damage, I share them to another one. I even installed an app in inReactOS and used in WindowsXP.
Latelly, I've been trying to Multi boot, directly between XP and ReactOS. I am using the BOOT.ini ain XP and Frldr.ini in ReactOS, been editing them in order to try and multiboot, but i think i'm far from beiong able to do it.
Hope i Helped! Doubts, just ask
P.S: Remember of the Alpha Stage, between virtual machines and the actual machine, I noticed tuff diferences, that go from graphics to Explorer bugs. That's why i Manily use the virtual machine
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