Q: In a recent column (tinyurl.com/zw24yu4), you mentioned several older Apple products that can't be updated to iOS 10, the newest version of the operating system. Do these products face a higher security risk?

Jean Page, Minneapolis

A: There are two ways to look at the risk faced by the non-upgradable Apple gadgets — the iPad 2 and 3, the original iPad Mini, the iPhone 4S and the fifth-generation iPod Touch.

Because Apple provides security updates for older operating systems only when a big threat arises, you could argue that devices without iOS 10 face more risks than they did before.

But there never were a large number of security threats to Apple's mobile devices, and older gadgets may get some additional protection from an unlikely source: obsolescence. Because older iPads, iPhones and iPods that can't use iOS 10 are outdated, most won't remain in use much longer. As a result, there won't be enough of them to attract malware attacks.

How rapidly is the number of non-iOS 10 devices declining? By mid-October, a month after its release, iOS 10 was being used by 70.3 percent of currently active Apple mobile devices, according to research firm Mixpanel (see tinyurl.com/hqxfmud). About 24.7 percent of devices still used iOS 9. Devices using all previous versions of iOS accounted for only 5 percent.

Q: My Windows 7 PC, purchased in 2010, has recently begun taking a long time to start up. It takes two to three minutes for the disk drive to start running steadily. After that, everything works fine. Does this mean the PC's hard drive is failing?

Bill Diedrich, Minnetonka

A: There are several possible causes of a slow PC start-up. Here are a few you can check out:

• The disk drive could be failing. Watch for other failure symptoms, such as files that won't open or sounds such as clicking or grinding. For more symptoms, see tinyurl.com/anfddds.

• The disk could be fragmented. As the disk fills up with data, the PC breaks up new files into pieces that are stored on different parts of the disk. The drive takes longer to retrieve those scattered file pieces. Run the Windows Disk Defragmenter (see tinyurl.com/ho5mwh6.)

• Too many programs are running at start-up. The Windows "msconfig" program lets you limit the number of these programs (see tinyurl.com/ckrepk5).

For other possible causes, see tinyurl.com/lokts8a.

Q: When I use Microsoft Office 365 on my PC, the Outlook e-mail program doesn't work with my Comcast e-mail. I can send e-mail via Outlook, but I can't receive it. What's wrong?

Delmar Fischer, Jacksonville, Fla.

A: If properly set up, Outlook should be able to send and receive messages through your Comcast account. Try removing the Comcast account from Outlook, then reinstalling it. Follow the directions at tinyurl.com/hzkwtkj for setting up a Comcast IMAP (internet message access protocol) e-mail account. With IMAP, e-mail remains on Comcast's mail server, but can be read, deleted or saved as if it were stored on the PC, phone or tablet computer you're using.

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