Q After turning on my PC, I have more than 70 "processes" running in the background that appear to use lots of memory. This seems excessive, and I wonder if they slow the system down.

KEN HOFFMAN, MINNEAPOLIS

A Processes are small programs that work in the background to keep your PC operating. They are at least minimally active all the time, even when the computer appears to be idle. And, yes, these processes do use up some of your PC's memory, and in extreme cases they can slow down your computer.

But don't try to stop any process from running on your PC until you know what it does.

You can view the processes running on your PC by simultaneously pressing the control, alt and delete keys, then choosing "Task Manager" and selecting the "Processes" tab.

Looking at the list won't reveal much, because most processes have odd names that provide no clue about what they do. For example, the "svchost.exe" process is an important part of Windows, and stopping it will cause big problems. Firefox.exe is the Firefox browser, which you can stop at any time.

You can find out how vital each process is to the PC by checking out process definitions at www.liutilities.com/products/wintaskspro/processlibrary/system/ or www.neuber.com/taskmanager/process/. To stop a process, highlight it in Task Manager and click "end Process."

Q I've had quite a few problems with Microsoft's Internet Explorer 8 browser since I was prompted to upgrade. When I go to a different page of a website or switch websites, the browser quits working and I get a message that says "a malicious add-on" caused it.

But this now happens on secure banking sites and other sites where I had no problems before. I've tried to uninstall Internet Explorer 8 and to get rid of it by using System Restore to roll Windows Vista back to a time before I upgraded IE 8, but I've had no success.

RICHARD STOUT, HUDSON, WIS.

A Many people have had problems with Internet Explorer 8, including the situation you describe. Microsoft offers help with the problem at support.microsoft.com/gp/pc_ie_v8intro, or, alternatively, support.microsoft.com/kb/956197/LN/. While you normally can't uninstall Internet Explorer, Microsoft has made an exception for IE 8. If you want to uninstall it, see support.microsoft.com/kb/957700.

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