Follow these steps-
Boot the computer in Safe Mode.
Safe mode is a troubleshooting option for Windows that starts your computer in a limited state. Only the basic files and drivers necessary to run Windows are started. The words Safe Mode appear in the corners of your monitor to identify which Windows mode you're using.
1. Restart your computer.
Click the Start button, click the arrow next to the Shut Down button, and then click Restart.
2. Do one of the following:
· If your computer has a single operating system installed, press and hold the F8 key as your computer restarts. You need to press F8 before the Windows logo appears. If the Windows logo appears, you'll need to try again by waiting until the Windows logon prompt appears, and then shutting down and restarting your computer.
· If your computer has more than one operating system, use the arrow keys to highlight the operating system you want to start in safe mode, and then press F8.
3. On the Advanced Boot Options screen, use the arrow keys to highlight the safe mode option you want, and then press Enter.
4. Log on to your computer with a user account that has administrator rights.
When your computer is in safe mode, you'll see the words Safe Mode in the corners of your monitor. To exit safe mode, restart your computer and let Windows start normally.
To know more information on how to boot into Safe mode visit the following link:
http://windows.microsoft.com/en-us/windows7/Start-your-computer-in-safe-mode
Method 1: If the issue persists, perform Clean boot in Safe mode.
To help troubleshoot error messages and other issues, you can start Windows Vista by using a minimal set of drivers and startup programs. This kind of startup is known as a "clean boot." A clean boot helps eliminate software conflicts.
I would suggest you to boot the computer in clean boot i.e disable non microsoft services.
The purpose of disabling non microsoft services is to check if any of these services is
causing the issue.
Follow the steps below to boot the computer in clean boot:
Perform clean boot and check if you have the issue.
1. Click Start, type msconfig in the Start Search box, and then press ENTER.
User Account Control permission
If you are prompted for an administrator password or for a confirmation, type the password, or click Continue.
2. On the General tab, click Selective Startup.
3. Under Selective Startup, click to clear the Load Startup Items check box.
4. Click the Services tab, click to select the Hide All Microsoft Services check box, and then click Disable All.
5. Click OK.
6. When you are prompted, click Restart.
7. After the computer starts, check whether the problem is resolved.
Note : Reset the computer to start as usual
After you have finished troubleshooting, follow these steps to reset the computer to start as usual:
1. Click Start, type msconfig.exe in the Start Search box, and then press ENTER. If you are prompted for an administrator password or for confirmation, type your password, or click Continue.
2. On the General tab, click the Normal Startup option, and then click OK.
3. When you are prompted to restart the computer, click Restart.
If the issue is resolved check which third party is causing the problem, referring the link given below:
http://support.microsoft.com/kb/929135
Method 2: Also try to update drivers for the devices by following these steps:
You must be logged on as an administrator to perform these steps.
1. Open Device Manager by clicking the Start button, clicking Control Panel, clicking System and Security, and then, under System, clicking Device Manager. If you're prompted for an administrator password or confirmation, type the password or provide confirmation.
2. In the list of hardware categories, find the device that you want to update, and then double-click the device name.
3. Click the Driver tab, click Update Driver, and then follow the instructions. If you're prompted for an administrator password or confirmation, type the password or provide confirmation.
For more information visit the following link:
http://windows.microsoft.com/en-us/windows7/Update-a-driver-for-hardware-that-isnt-working-properly
Method 3: Check if there are any errors in the Event Viewer.
Applications and Services Logs vary. They include separate logs about the programs that run on your computer, as well as more detailed logs that pertain to specific Windows services.
1. Open Event Viewer by clicking the Start button, clicking Control Panel, clicking System and Maintenance, clicking Administrative Tools, and then double-clicking Event Viewer. If you are prompted for an administrator password or confirmation, type the password or provide confirmation.
2. Click an event log in the left pane.
3. Double-click an event to view the details of the event.
Method 4: To run the System File Checker tool, follow these steps:
1. Click Start Collapse this imageExpand this image, and then type cmd in the Start Search box.
2. Right-click cmd in the Programs list, and then click Run as administrator. Collapse this imageExpand this imageIf you are prompted for an administrator password or confirmation, type your password or click Continue
3. At the command prompt, the following line, and then press ENTER:
sfc /scannow
Method 5: Also run a online virus scan and check if the issue persists.
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