QI returned my printer, an HP Officejet Pro 8600 Plus, because it sometimes printed in a foreign language. Now a second unit periodically does the same thing.

I've spent hours talking to HP help desk people about reloading the printer software and trying other fixes. I'm convinced they can't correct it. The strange thing is that, on the second try, the print comes out in English.

Could this be caused by malicious software?

I've e-mailed a printing sample so you can see what I mean.

DENNIS ZYLLA, Minneapolis

AYour printer isn't printing in a foreign language; it's printing gibberish.

Assuming it's a technical problem, HP offers several potential ways to fix it. But the real problem may be that you've downloaded some malicious software that is causing your printer to act that way.

HP's troubleshooting guide (see tinyurl.com/cf67rbl), shows you how to diagnose potential causes. It's possible, for example, that the correct printer hasn't been selected, that the file you're printing is flawed or that the printer's USB connection to the PC is loose or malfunctioning.

But articles on the tech websites ZDNet (tinyurl.com/cp5zkew) and CNet (tinyurl.com/6sma2ce) suggest you might have inadvertently downloaded a malicious program called "Trojan.Milicenso" that's been around for two years.

While the purpose of the malware is to misdirect your computer online, a side effect is to create a file on your computer that Windows then tries to print. Because the file consists of computer code, the printout is gibberish.

Before trying the HP fixes, download and run the free version of security program Malwarebytes (go to tinyurl.com/cwbd73f) and click "free download").

QI'd like to increase the speed of my eight-year-old HP PC. Some TV commercials promise their software can boost speeds. Are these ads credible? Or is there another way to juice my PC at least a little bit?

ANDY ANDERSON, PLYMOUTH

ASkip the TV software. Microsoft offers tips (see tinyurl.com/ct9umtx) on how you can make your PC run a little faster by getting rid of junk software that might be slowing things down, using a flash drive as extra PC memory or cleaning up a cluttered hard disk drive.

But those things are unlikely to make an eight-year-old PC run much faster. Today's software -- Web browser, photo viewer, music player or word processor -- demands more computing power than your PC was designed for. It may be time for a new PC.

E-mail tech questions to steve.j.alexander@ gmail.com or write to Tech Q&A, 425 Portland Av. S., Minneapolis, MN 55488. Include name, city and telephone number.