Acronis Partition Expert Trial Get it here. http://us2.download.acronis.com/partitionexpert2003_d_en.exe when resizing partition using Ubuntu Linux, I had it installed on virtual I got operating system not found error.. even though I resized using free space... so thats the last time I do that ... one I did resize, it said OPERATING SYSTEM NOT FOUND SAFE MODE, last known good configuration and other stuff will not work.. 1.I BOOTED FROM XP CD, ensuring cd was a boot device.. (on dell inspiron 6400 you press f12 and then select cd-rom from the device list) 2. see if Repair Installation is available if yes.. do a repair installation I guess... if no... restart machine, boot from XP cd again, then go to RECOVERY CONSOLE (press r when prompted) 3. in recovery console it should fix c: and say unreadable perhaps... when you try dir .. type: fixmbr fixboot it will say ONLY do this if you can't boot, which should be the case. 4. could not load autochk.exe now you shoudl be able to see the windows loading screen. The problem is a HIDDEN partition. when windows loads it will say could not load autochk.exe http://www.pchell.com/support/autochknotfound.shtml Now I have a LAPTOP with no floppy drive, and I wasted a good at least 10 CDs trying to get the thing to boot, and fix what I needed. Basically you need any tool that can create a bootable CD(for laptops ..) allowing you to hide or unhide partitions i.e. changing the partition type number. Solution: GET ACRONIS PARTITION EXPERT I am not sure if the trial can burn to a cd, but the professional version can, and then you boot from this CD, and follow the instructions at http://www.pchell.com/support/autochknotfound.shtml which basically involve changing the partition to NTFS type(assuming it was NTFS originally I guess..) 0x07 if you tried to install Ubuntu Linux the number will be some Linux number like 0x17... so change to 0x07 Alternate Solution: get a bootable floppy with ptedit and boot from it ftp://ftp.symantec.com/public/english_us_canada/tools/pq/utilities/ptedit.zip The number here should generally be 07 (hex), meaning the partition is an "Installable File System", in other words a bootable drive. If its anything else its not bootable. Using your tab key, tab down to the Type box and hold down ALT + T to open the Set Type menu, then with your keyboard arrow, select 07, tab down to Ok and press Enter 8) Hold down ALT + S to Save Changes to the partition table and then Press CTRL +C to exit out of the program. COnclusion: the problem is if the number is not 07... it is a hidden partition.