Concerned you may have a malware / virus infection , then run the Microsoft Malicious Software Removal Tool to check and clean up any infections on your computer.
Every month Microsoft with Windows Update update a program called the Microsoft Malicious Software Removal Tool.
This is a companion tool to your antivirus product and is not a replacement.
The Microsoft website states:
“The Microsoft Malicious Software Removal Tool checks computers running Windows 8, 7, Windows Vista, Windows XP, Windows 2000, and Windows Server 2003 for infections by specific, prevalent malicious software—including Blaster, Sasser, and Mydoom—and helps remove any infection found.
When the detection and removal process is complete, the tool displays a report describing the outcome, including which, if any, malware was detected and removed.”
To be safe you could run this once a month in deep scan mode.
To activate and run this tool ( you will not find it in the program list ) in Vista and Windows 7 , 8 go to the search box and type in mrt.
In Windows XP , start run , type mrt
Press next and you will see the following screen
Select that you want to do a full scan , press next and once it has started just let it run.
A full scan is likely to take several hours so just leave the computer to run.
It will thoroughly scan your computer and remove anything that it finds , a comprehensive list of what it detects and removes can be seen in the software.
Remember this is no substitute for an antivirus program.