System Hangs Before Windows Startup Screen (Progress Bar)

Hi guys,

I would like to know why windows stops loading before the start up
screen or the windows progress bar when i use restart in windows or if i
have installed some updates to apps that need restart.

It is not the case when I push the restart button on my computer case.
It loads without hanging.

It used to be okay when i first installed XP and then came a time that
this happened so i upgraded to vista but same thing still happens even
after upgrade.

Thanks in advance.


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jamoraquai