I frequently recommend the free Malwarebytes security program to clean PCs infected with viruses or other malicious software. So I was puzzled when two readers said that it disabled their Google Chrome browsers.

The problem seems to be linked to a trial offer from Malwarebytes. And not everyone is affected.

Here's the gist: I recommend the free version of Malwarebytes (see tinyurl.com/jsdacdk), which doesn't have any adverse effect on Chrome. But the free version of Malwarebytes currently includes a 14-day free trial subscription to Malwarebytes 3.0 Premium, which normally costs $40 a year. It's this trial version that's automatically installed on your PC, and it includes an "anti-exploit" feature that sometimes prevents the Chrome browser from functioning.

What can you do? After you install the free version of Malwarebytes, you can opt out of the 14-day trial. To do so, go to "settings," then click on "my account." At the bottom of the page, click on "deactivate premium trial." You' will then have the basic free version of the program.

If you have already had Malwarebytes disable the Chrome browser, try adding Chrome to a list of programs that aren't monitored for malicious activity. To do that, go to "settings" in Malwarebytes and select "exclusions." At the bottom of the page, click "add exclusion," and choose "exclude an application that connects to the internet." Click "next." Click "browse," then at the left of Windows Explorer choose the "C:" disk. On the right of Explorer, double-click "program files (x86)." Double-click the Google folder, then the Chrome folder, then the Application folder, then the Chrome icon. Click OK.

If that doesn't work, try uninstalling Chrome, then using another browser to reinstall it. But this time use the "alternate Chrome installer" link at tinyurl.com/lmy49sl. This seems to eliminate the Chrome-Malwarebytes Premium software conflict for most people.

Q: I use Microsoft Office 2007, but I understand that technical support for it will end this year. I'm not in a position to buy a new version of Office, so how risky will be it be to keep using Office 2007? Is there free software that I could use instead?

Robert Heston, Atascadero, Calif.

A: Microsoft will no longer provide security updates for Office 2007 after Oct. 10, which means your software will be at risk after that.

How risky will it be to continue using Office 2007? Attacks on individual Microsoft programs aren't as common as attacks on Windows, but they do happen. Between January and April this year, hackers attacked a newly discovered vulnerability in Microsoft Word that affects all versions of Microsoft Office, including the newest one, Office 2016 (see tinyurl.com/nxmda47). Malware contained in e-mailed Word documents allowed other harmful software to be downloaded to the victims' PCs. Microsoft is expected to issue a security patch to prevent the attack from happening again, so you will be safe. But after October, you won't have that assurance.

There are several free alternatives to Microsoft Office, including Google Apps, LibreOffice 5 and Apache OpenOffice 4 (see tinyurl.com/n4kmh6j).

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