Hi again
Which AntiVirus are you using ?
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Try the following: ( Copied .....saves typing :) )
Open System Configuration by clicking the Start button http://res2.windows.microsoft.com/resbox/en/windows%207/main/4f6cbd09-148c-4dd8-b1f2-48f232a2fd33_818.jpg, clicking Control Panel, clicking System and Security, clicking Administrative Tools, and then double-clicking System Configuration.* http://res2.windows.microsoft.com/resbox/en/windows%207/main/18abb370-ac1e-4b6b-b663-e028a75bf05b_48.jpg If you're prompted for an administrator password or confirmation, type the password or provide confirmation.
Click the General tab, click Diagnostic Startup, click OK, and then click Restart.
If the problem occurs now, then basic Windows files or drivers might be corrupted. ( suspect it is a driver )
If this is the case we may have to look at the "Startup Repair" option
If the problem does not occur, then we will need to use Selective Startup mode to try to find the problem by turning individual services and startup programs on or off.
This will be a long process.