Q: I've been getting unexplained pop-ups on my Windows 10 PC. One says, "How do you want to open this file?" when the file name extension (letters after the dot) is ".vdykyvf". I can't determine what kind of file has that extension name.

The other pop-up is related to Microsoft OneNote, a program I've never used. I'm offered "screen clippings" to click on, but when I do, the entire screen becomes light blue. I can close it by clicking on a OneNote icon in the toolbar. What's causing these problems? Are they related?

Carolyn Fies, Birdsboro, Pa.

A: You probably have a virus on your PC that's generating the "open this file" messages. The OneNote pop-up is legitimate, but you can turn it off.

Normally, a "How do you want to open this file?" message pops up when your PC doesn't know which program opens a legitimate type of file. But you are correct that there is no file name extension called ".vdykyvf". This phony file extension is most likely generated by a malware program that is trying to fool you into activating it. Download the free version of Malware­bytes (see tinyurl.com/jsdacdk) and make sure your antivirus software is current.

OneNote is a program that allows you to combine text, drawings, web pages and other information (some of these elements are called "screen clippings"). The "Send to OneNote" pop-up you are seeing is a "helper program" for OneNote. To make the pop-up disappear for good, click the box next to "Start with OneNote," then click "exit."

Q: I have a Dell Inspiron 11 3000 laptop PC with a 32-gigabyte Embedded Multimedia Card (eMMC, a computer chip memory that's faster than a hard disk but slower than its cousin, the chip-based Solid State Drive). Nearly all the eMMC's storage space is used by Windows 10 and the programs that came with the PC, so I don't have enough free memory to install a Windows update. I plugged in a USB flash drive in hopes the PC could use the extra memory for the installation, but it didn't work. What can I do?

Ed Lavallee, Manchester, N.H.

A: A flash drive can provide extra memory for the installation, but more setup is needed.

You will need two empty 16-gigabyte flash drives, and the use of another PC to download the necessary Windows 10 installation files to one of the flash drives. You can then put one of the flash drives in each USB port of your PC. The flash drive containing the downloaded files will help install the Windows 10 update on your eMMC, and the other flash drive will act as extra computer memory during the installation.

Follow the directions at tinyurl.com/yc6w38rf to download the necessary files (from tinyurl.com/ycm3bktz) and to set up your PC for the installation.

Q: I inherited an iPhone 3G. But its memory is completely filled with music, which prevents me from taking any photos. How can I delete all the music?

Glenn Scott, Colorado Springs

A: You can use the phone's "Settings" app to delete all the songs at once (see tinyurl.com/y8brac4r). If that doesn't work, you can perform a "hard reset" that will return it to its factory settings (see tinyurl.com/ya2fccgx).

E-mail your tech questions to steve.j.alexander@gmail.com. Include name, city and telephone number.