When repairing a PC by either trying to shutdown a virus, trying to remove adware/spyware/malware or just trying to get a speed increase you need to shut down processes that run in the background. It is often nessessary to know the bare minimum processes which Windows needs to operate and it is sometimes difficult to know which ones are which, here is a list of the essential processes that Windows needs to run correctly.

• System Idle Process
• explorer.exe
• taskmgr.exe
• spoolsv.exe
• lsass.exe
• csrss.exe
• smss.exe
• winlogon.exe
• svchost.exe - (There will be a few of these)
• services.exe

By shutting down anything other than these processes, stand alone Windows should operate fine, however if any of these processes are shutdown, Windows will start to become unstable or unusable.

On most computers there will be multiple instances of svchost.exe, these control various connections on your computer wether its to the internet or within a lan. It is usually safe to switch off some of these however its not easy to determine which ones operate what so its best to leave these alone. In regards to Windows 98 and Windows ME, you can shut down everything except Explorer and SysTray to keep it running.

To shutdown a Windows process, Press Ctrl+Alt+Delete, Goto the Processes Tab, Select a process and click End Process.

If you are not sure what a certain process does, then I recommend Wintasks which is a library that lists what each task does, its threat level and makes it easy to determine what is running on your (or your clients computer).