EDIT: post edited, responce to other quote moved HERE can you try doing it from safe mode please? Windows XP If Windows XP is the only operating system installed on your computer, booting into Safe Mode with these instructions. If the computer is running, shut down Windows, and then turn off the power Wait 30 seconds, and then turn the computer on. Start tapping the F8 key. The Windows Advanced Options Menu appears. If you begin tapping the F8 key too soon, some computers display a "keyboard error" message. To resolve this, restart the computer and try again. Ensure that the Safe mode option is selected. Press Enter. The computer then begins to start in Safe mode. you will know because the words 'safe mode' will be in all four corners. When you are finished with all troubleshooting, close all programs and restart the computer as you normally would. when you open in safe mode, retry the steps i said previously, to start a disk check, located in THIS POST If the system wont even let you do a simple disk check, i'm afraid it looks like you may have to do a reinstall, as monsta suggested. Lets see if we can get it started in safe mode first tho. let me know how you get on, or if there are any problems.