I am unable to boot into my Boot Camp partition from Parallels. After authenicating with my password, I get a drop down dialog box with the message "Unable to open disk image Boot Camp!" I have gone back and deleted the Windows Parallels Tools (after first deleting the Parallels Tools from withing the guest OS (WinXPro) and re-installing. I have run several new setups using the Boot Camp disk selection. Nothing I do seems to help. If you have had a similiar situation and were able to resolve it, please let me know.
Does your bootcamp partition disappear after you get that message? I had a similar occurance: http://forum.parallels.com/showthread.php?p=31540#post31540 All I have to do though is reboot MacOSX and it's back to normal. I'm not sure what's the cause and any further insights would help!
I converted my FAT32 Boot Camp partition to NTFS using the Windows console command 'convert' (convert c: /fs:ntfs.) This solved my problem and I can now boot into Boot Camp through Parallels.