While my sister was using the PC, it restarted suddenly. It would boot until it 
shows the Windows loading animation and then restart again.
I tried repairing the Windows installation with a setup cd but it would ask for the administrator’s password which i forgot.
I had to remove the previous windows installation and install it again. Grrrr
If you just formatted your PC and don’t know from where to start to make it functional again, follow this guide.
Hey men sorry for your PC, next time you don’t remember administrator password use Trinity Rescue Kit usefull for that, rescue and maintenance… 😉
Trinity would be of no use as windows itself didn’t start. Now, i hope to remember the password i set.
Sure my friend, you are right the only solution is to format, thank God there are the partitions to backup all… 😉