Windows 8 Pro Upgrade Fails @ 90%

Hi, I have upgraded two of my PC's flawlessly now but my HP G61 110SA laptop which has Windows 7 X64 Ultimate on is failing at 90%. It gets to 90% and states Windows is going to restart shortly but does not and then I get the dialogue Windows 8 upgrade has failed and is reverting back to Windows 7. I have used upgrade assistant and uninstalled any software it flashed up and on other sites I...