Using the System Configuration utility, you can disable all start-up programs (Diagnostic startup) to see if any program is causing the problem.
To perform a diagnostic startup, follow these steps:
For windows Vista
Click Start, type msconfig in the search box and then click OK.
On the General tab, click Diagnostic Startup, and then click OK.
Restart your computer.
For windows XP
Click Start, click Run, type msconfig, and then click OK.
On the General tab, click Diagnostic Startup, and then click OK.
Restart your computer
If the problem does not occur, run the program again and choose Selective startup mode to try to find the problem by turning individual services and startup programs on or off.
For more information click here
http://support.microsoft.com/kb/310560
(this guide for windows XP, but applies to Vista as well)
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Also there are other useful tools in windows , such as Windows Reliability and Performance Monitor which provides a system stability overview and details about events that impact reliability.
To use this program do as follows.
From windows go to Start, the put mouse cursor on Computer (or My Computer in XP) and then press right button on the mouse and click Manage , once the programs opens up, In the navigation tree, expand Reliability and Performance, expand Monitoring Tools, and click Reliability Monitor.
Based on data collected over the lifetime of the system, each date in the System Stability Chart includes a graph point showing that day's System Stability Index rating.
The System Stability Index is a number from 1 (least stable) to 10 (most stable) and is a weighted measurement derived from the number of specified failures seen over a rolling historical period.
Reliability Events in the System Stability Report describe the specific failures. Look at chart can you see any x and i, below 0 . If yes then double click on it. At the bottom it gives more information about the about the cause of Error event, whether it was Application , Hardware, or miscellaneous Windows Failure .
For more information about interpreting the System Stability report, click here
http://technet.microsoft.com/en-us/library/cc749583%28WS.10%29.aspx
Also look at the even viewer more information click here
http://technet.microsoft.com/en-us/library/cc766042%28WS.10%29.aspx
---------------------------------------------------------------------------------------If the problem persists, then try installing the components one at the time until you find out which is the conflicting one.
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