Q: I'm using PC-based Microsoft Office 2010, which will stop receiving security updates in October. The company is directing me to switch to Microsoft 365 (the new name for the online Office 365). But I'm not sure I want to switch. Will the online version be able to read all my existing Word documents? Will I have to pay for it, or are there free downloads?

William Carlson, Vadnais Heights

A: You don't need to switch from PC-based to online Office software. Each has its merits, and both are backward-compatible so they can read your existing Word files. The choice you make will revolve around cost, convenience and the way you like to work. Here are the options:

• Traditional PC-based Office software for which you pay a one-time purchase fee. You don't need an internet connection to use it. The least expensive version is the $35 to $150 "Home and Student," which you can install on only one PC. You will get program updates until October 2023 and security updates until October 2025. (See tinyurl.com/yb99529j).

• A free version of Office, called "Office on the web" (formerly Office Online), that you use via a browser. There's no way to use it offline. To use the Word files on your PC, you will need to upload them to Microsoft OneDrive, an online storage service (see tinyurl.com/y7wvdjag). If you want to store the files on your PC again, you can copy them from OneDrive. Microsoft continuously updates the online software. (See tinyurl.com/yc6m36c3).

• Microsoft 365, an online product for which you pay a subscription fee each year. Because the software also downloads to your PC, you can use the programs both with or without an internet connection (but you must go online at least once every 30 days or your PC-based software will stop working). The least-expensive version, called Personal, costs $70 a year, and can be used by one person. There is no end-date for Microsoft's technical and security updates (see tinyurl.com/yaacqhg5). Go to tinyurl.com/y8tkv7yw to further compare PC-based Office and Microsoft 365.

Of the three options, Microsoft is pushing 365 the hardest, and it's not hard to see why. The company gets a steady, predictable stream of revenue that doesn't require issuing new software versions every few years. Microsoft has also encouraged the shift by reducing the security life span of the PC-based Office suite to seven years from 10.

Q: We had our PC cleaned after it froze up and displayed unusual messages. At the time, we were told that the PC's processor and disk usage were really high. After two trips to the repair shop, the problem was fixed, but now we are forced to log in to the PC by simultaneously pressing the CTRL-ALT-DEL keys. What's wrong?

Jan Drigans, New Brighton

A: This is an optional security setting that's designed to prevent your PC password from being stolen by malicious software. I suspect it was enabled by your repair technician because your PC displayed malware symptoms — high processor and disk use and the appearance of strange messages. To turn the setting off (and return to logging in the normal way), follow the directions at tinyurl.com/ycqzvmzy — use the suggested "netplwiz" command to access the settings.

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