Q: We use Google Drive and Microsoft OneDrive to continuously back up the files on our two computers. If our computers were infected with malware or suffered a ransomware attack (in which files are encrypted until you pay a ransom), would these cloud backup services be affected, too?

Also, can I recover cloud-based files that I accidentally delete?

Doug Johnson, St. Louis Park

A: If your PC is attacked by malware or ransomware, your damaged or encrypted files would be automatically backed up to Microsoft OneDrive or Google Drive, making the problem worse.

But it would be only a temporary setback, because both online services keep backups of previous versions of your files (from before the attack on your PCs began.)

As a result, once the malware or ransomware was removed from your computer you could download untainted previous versions of your files from Google Drive and OneDrive. To learn how to do that, see tinyurl.com/yxagtbug and tinyurl.com/yy33gqp6 for Google Drive, and see tinyurl.com/y63sa9bd and tinyurl.com/y5oagtl7 for Microsoft OneDrive.

Both online storage services have their own trash folder or recycle bin. So, if you accidentally delete an online file you can get it back from the trash for up to 30 days.

Q: Photos that I text from my iPhone 6 are being sent via iCloud instead of directly from my phone number. But not all my text recipients can access those iCloud photos. What can I do?

Terri Romano, Metairie, La.

A: Your Apple texting service, called iMessage, probably isn't set up correctly. As a result, your text messages are being rerouted through iCloud. To the people who receive your texts, the messages appear to come from your iCloud e-mail address.

But if you make some settings changes, your texts will be sent from your phone number. Go to Settings and click Messages. Use the "switch" to turn on iMessage, and make sure that "Send & Receive" shows your phone number. (If your phone number isn't visible, click "Send & Receive." In the next menu, add your number under "You can receive iMessages to and reply from." Switch the check mark from "use your Apple ID for iMessage" to your phone number.)

Q: I have three Windows 10 PCs and one Windows 7 PC on my home network. I know that the Windows 7 PC is vulnerable to hacking because Microsoft stopped providing security updates in January. But I've kept it because it handles the online program guides for our TV and another PC that we use for home theater. Is there a way to isolate the Windows 7 PC from the others on the network, so that a hacker attack on it won't affect the other PCs?

Michael Kehoe, Minneapolis

A: All your PCs share an internet-connected home network, which means they can all talk to the outside world and to each other. If your Windows 7 PC was hacked, it could be used to attack your other PCs as well as to cause trouble online. While there are technical ways to isolate your Windows 7 PC from the others, I don't recommend them for the average person. (For details, see tinyurl.com/ya4ttl3x and tinyurl.com/y4x87gpk).

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