Dual Booting (Xp & Vista) + 2nd HD = Error, Please help

Here is the setup. I have XP and Vista dual booting on one hard drive. No problem, everything is fine.

Then when I had a second HD for storage and format it in Vista, everything is fine, I can move files in and out of it, no problem.

Then I shut down and boot up into XP. When I go to access the drive its says its unreadable.

Then I shut down and go back into Vista, it now says its unreadable. So I have to do a full reformat for it to work again....

Anyone know whats going on...???.....its like XP is messing it up or something. Please help!!!

Thanks,
Kyle

Thanks for the reply. The first time I formatted it with partition magin I did it usinf NTFS and still got the error. The I tried Fat32. It seemed to work, but I am still not convinced that I wont lose data later on.

It was also a little buggy with XP and Vista together on a raid 0+1. So I have decided to redo the whole thing and not use Vista. Also, I have an X1900 AIW and the TV Tuner doesnt work in vista, ATI doesnt have drivers for it. So I am going to stick with XP.

Thanks for your help.
Kyle