Processes not closing

I'm having a bit of a strange issue;

Quite a few processes aren't closing when I close their applications.

I close the window or shut it down, yet when I check task manager the process lingers, and causes the program to malfunction when I start it again.

I have to exit the process and restart it to get it going properly.

They seem to be mainly processes with high memory usage:
outlook.exe
firefox.exe
hl2.exe (CS: Source)

My PC is a Quad Core with 4GB of RAM, 750 GB hard-drive etc, Windows XP...

Got any ideas?

 

You may be infected with Malware...
You need to go here;
http://forums.techguy.org/54-malware-removal-hijackthis-logs/
Read all the sticky posts and don’t do anything until instructed to by an Expert.


Please be patient, there are a lot of people waiting for help as this is a big problem, so spend your time researching, Security Help Tools and any thing else that you can find to help you learn how to avoid this in the future.

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