Q: My PC seems to be running slow, so I've been looking for unnecessary programs that might be running in the background of the computer's main software. I've included a list of programs that the PC's "Windows Task Manager" says are running in the background, and many of them I can't identify. Which of these programs should I stop?

Jim O'Toole, Eden Prairie

A: None of the background programs in your list are consuming much of your PC's RAM (random access memory.) So your PC is more likely being slowed by malicious software or junk programs that you've accidentally downloaded.

Run the free version of the Malwarebytes security program, which will find and eliminate that unwanted software. See tinyurl.com/gtvjx33, and under "for home" click "download free version." But there are also a couple of things to remember:

• Trying to fine-tune the list of background programs running on your PC is likely to cause trouble, because most of that software is important.

• If your security software conflicts with Malwarebytes, add the latter to the exceptions list in your anti-virus software and firewall program. Then, in Malwarebytes, exclude your security program from being scanned for unwanted software. (Security software interprets scans of itself as malicious activity.) For details, see tinyurl.com/jqagpar (Mbam stands for Malwarebytes.)

Q: Recently, I've started having wireless Internet problems when my Windows Vista PC comes out of "sleep mode" after being inactive. I get a "server not available" message, and can only reconnect to the wireless router by turning the PC's Wi-Fi off and then on again. What's wrong?

Rolf Sumstad, Plymouth

A: Because it's a new problem, try returning the Windows Vista settings to the way they were before the trouble started. Click Start, type "system restore" in the search window and press the Enter key. In the resulting menu, select "choose a different restore point" and click Next. From the list, choose a restore point (calendar date) before the problem began and click Next. After you confirm your choice, the PC will restart with the old settings active.

Q: You recently mentioned a website that told which Dell PC models were suitable to be upgraded to Windows 10. Is there a similar list for HP computers?

Ron Sternal, St. Louis Park

A: HP doesn't offer a list, but says most of its PCs sold after August 2013 are Windows 10 compatible. For those models, HP provides Windows 10 software drivers that control PC devices and accessories. For upgrade details, see tinyurl.com/o79he3r.

E-mail tech questions to steve.j.alexander@gmail.com or write to Tech Q&A, 650 3rd Av. S., Suite 1300, ­Minneapolis, MN 55488. Include name, city and telephone number.