Q: I bought a Linksys router and then switched our computers and phones (but not our Roku TV device) to Norton security software. Recently, my wife and I received Norton warnings on our phones that our Wi-Fi had been compromised, even though Norton also showed that our Wi-Fi had strong encryption. Then I read that the Russians have for years penetrated Western computer networks, and that even homes are at risk (see tinyurl.com/ycytqzkp). Have we been affected?

Steven Madole, St. Paul

A: Probably not. The Norton warning most likely means that your Wi-Fi router hasn't been updated to protect against the "Krack" security vulnerability that was discovered last year. Updating the router's software should resolve the issue.

The Krack (Key Reinstallation Attack) vulnerability sent shivers through the tech community because it revealed a basic security flaw in the WPA2 encryption technology used by most consumer Wi-Fi devices (see tinyurl.com/yah6gous and tinyurl.com/yb6aej2h). As a result, a Wi-Fi device — such as a router, a PC, a phone or a TV streaming device — could have had its Wi-Fi transmissions tapped by someone nearby, allowing personal data to be stolen. In some cases, compromised Wi-Fi could have been used to secretly install malware on a device.

Fortunately, it appears that the Krack vulnerability was never exploited by malicious hackers. Nonetheless, most device makers have updated their software to eliminate the potential threat.

In your Wi-Fi network, the Linksys router may be the last device to need one of these software updates. You can use your router's controls to update its software manually, or to set up automatic updates (see tinyurl.com/yct3pn9u). Or you can download an update from a Linksys website devoted to fixing the Krack vulnerability (see tinyurl.com/yd9k4cpg).

Q: My Windows 10 PC is using a lot of RAM (random access memory), even when idle. RAM usage sometimes reaches 98 percent. The Microsoft Edge browser is one of the biggest memory users; others are Microsoft OneDrive and EEventManager Application. What's going on?

Dennis Le Vesque, Brooklyn Center

A: Most of the RAM is probably being used by Microsoft's Edge browser, which consumes a lot of memory, even when a PC is idle.

Why? The Edge browser and the Windows 10 Cortana digital assistant operate together in the background of your PC, reporting back to Microsoft the data that Cortana collects on your Web browsing. To minimize this activity, clear the browsing data collected by Edge and alter Cortana's settings (see tinyurl.com/yake8zk9). Or use a different browser.

Microsoft OneDrive, a cloud storage service, runs constantly on your PC, whether it's active or not. To turn off OneDrive, right-click its toolbar icon and select "quit OneDrive." (For other fixes, see tinyurl.com/y8j6397f).

"EEventManager Application" is Epson printer software. But some malware masquerades as the Epson program, and malware can boost RAM memory use. For safety, run the free version of the Malwarebytes security program (see tinyurl.com/jsdacdk).

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