Q: I downloaded a new software driver that a pop-up message said I needed. Because the message contained the Microsoft logo (it was from a Microsoft Gold Certified Partner), I figured it must be OK. Along with the driver came a program called SlimCleaner Plus, which I haven't used.

While I'm not having any problems, I'm concerned that I can't uninstall the driver or the program. What should I do?

Francis Coz, Eveleth, Minn.

A: You were right to be suspicious of software that can't be uninstalled, although in this case no harm was done. SlimCleaner Plus is a legitimate program that exhibits some bizarre behavior because of the way it works.

The software is a $30-a-year PC utility program that eliminates unnecessary files that can slow down a PC (the download and its scan of your PC are free, but it will only delete useless files if you pay). To do its job, the program runs invisibly in the background of your PC. It can only be uninstalled if you first turn it off. That's a safeguard to prevent the software from being interrupted while it works with critical files such as the Registry that contains PC settings.

Unfortunately, the installation directions for SlimCleaner Plus don't tell you how to uninstall it. To turn the program off, right-click its icon on the right side of the Windows taskbar, then choose "shut down" on the resulting menu. Once you do, both the software driver and program should be easily uninstalled. (See tinyurl.com/ppq9kfe for more details on how to uninstall the software if you are using Windows Vista, Windows 7 or Windows 8.)

In the future, I suggest that you be suspicious of any website message that urges you to download unfamiliar software. Anyone can steal a familiar logo to make a pop-up message (or a malicious e-mail) look legitimate.

Q: The software I previously used to stream photos and music from my Windows 8.1 PC to my HDTV is no longer available. I've been trying unsuccessfully to replace it with the Google Chromecast device that plugs into one of the TV's HDMI ports. Do you have any suggestions on how to make it work?

Charles Totty, Baton Rouge, La.

A: Google Chromecast, a Wi-Fi device that moves video and other files around your home network, can be set up in six different ways, depending on what you're trying to accomplish (see tinyurl.com/l949wa5). In nearly all situations, you must be using a Wi-Fi router that operates in the 2.4 gigahertz part of the radio spectrum.

I suggest you use method one (see setup details at tinyurl.com/k2nhkrt), which streams video, music or photos from your PC's Google Chrome browser to your TV's Chromecast device. The video will be low-end HDTV quality, or 720p. The "p" is for progressive scan, in which 720 horizontal lines on the screen are refreshed progressively one after the other. The highest-quality HD signal is 1080p, which stands for 1,080 lines that are progressively displayed.

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