Alexander: If YouTube videos halt, give this a try

Q: I have a problem playing YouTube videos on my computer. Whenever I click on a YouTube link or just use the YouTube website, the first part of the video immediately loads. But then the gray bar showing the download progress simply stops at the same spot and I have about 30 seconds of the video. This happens about 90 percent of the time. Other times, everything seems to work and I get the complete video.

I don't think this is caused by my PC, which is newer, or by my Internet connection, which is from the cable company. The problem also seems unrelated to whether or not someone is using another PC on our home Wi-Fi network. Any suggestions?

Tom Reynen, Bloomington

A: Experts suggest several steps you can take.

Test the speed of your Internet connection at speedtest.net. You need about a 5-megabit (5 million bits per second) download speed for good video streaming. While you probably have more than that with a cable Internet connection, the speed isn't constant, and can vary depending on how many other people are using the service at the same time.

Don't let other PC programs, browser plug-ins that update the weather or other computers on your home network siphon off part of your Internet capacity while you're trying to stream video. Turn them off.

Download updates for your browser, then restart your PC so the changes will take effect.

Don't try to watch the video while it streams; let the entire video load first.

Q: While trying to sign in to my PC, I got a message that said "The User Profile Service failed the logon. User profile cannot be loaded." What would cause this to happen?

My solution was to create a new user profile with my PC's "administrator" account, but then I had to move some of my files (I still haven't found them all) and reload some of my programs to work with the new profile. Is there a way to go back to my old user profile?

Bob Olson, Richfield

A: A user profile can become corrupted, and thus not usable, if Windows isn't configured properly or if some files are accidentally deleted. Other times, a user profile may be only temporarily unavailable, such as when an antivirus program is running.

You can use a Windows search to find lost files. In Windows 7, go to the Start button and type the file name in the space that says "search programs and files." In Windows 8, press the "ctrl" and "esc" keys simultaneously, and start typing the file name.