Can't shutdown my pc

After using my system i am trying to shoutdown but its not shouting down why? give some suggestion to resolve this problem.

thanks

v.selva

First, run anti-virus software. Make sure the system is virus free. I use AVAST FREE. register, download , run, schedule a boot scan.

Any new Hardware or software can cause a glitch in the services to be terminated when you shut down. Worms and Trojans are notorious for causing a pc to Hang.

Next, you must remember that the Windows operating system is not a single program, but rather a collection of individual services. Each of these services must be stopped during shut down. Therefore, a glitch related to any one of the services may prolong the shut down process or cause the shut down process to fail completely.

Many people have claimed that the Nvidia Driver Helper Service (used with Nvidia video cards) causes extremely slow shut downs. However, this is one of those cases in which an updated video driver usually solves the problem. Other people have mentioned that disabling the terminal services greatly expedites the shut down process. The Terminal Services are used for remote assistance, remote desktop, and fast user switching. If you do not use any of these features, then the Terminal Services can be safely disabled. You can access the services console by entering the SERVICES.MSC command at the Run prompt.
Another potential cause of slow system shut downs is that Windows contains an option to erase the system’s virtual memory and system hibernation cache at shut down. These security features are disabled by default because they take a long time to complete, and cause the system shutdown to look like it has frozen. Although these features are disabled by default, some privacy software will enable it.

To determine whether or not these features are enabled on your PC, enter the GPEDIT.MSC command at the Run prompt to load the Group Policy Editor. Now, navigate through the console tree to Computer Configuration | Windows Settings | Security Settings | Local Policies | Security Options. At this point, locate the Shutdown: Clear Virtual Memory Pagefile option in the column to the right and verify that it is disabled, as shown in Figure C. If this option is enabled, you can disable it by double clicking on the setting and choosing the Disabled option.

Jamesangus,
Hold the power button down for 10 seconds or a little more and if that doesn't shut it off? Disconnect the power cord. Either of these methods should only be used as a last resort in the order posted.
Let us know if you have any problems when you start it back up?