Q: I use Windows 10 System Restore, which will allow me to return the PC's settings to an earlier time if I run into trouble. I create a new "restore point" (a calendar date to which the PC could return) every day, but it disappears within 24 hours. What's wrong?

Jeremy Hollerman, Edina

A: System Restore is one of the most valuable protection features of a Windows PC. If a calamity befalls your PC today, it's your time machine to escape into the past.

Fortunately, there are several ways to fix System Restore. The easiest is to scan your PC for malware (no antivirus program catches everything.) Malware might erase your system restore points to protect itself from being removed (returning to an earlier date erases everything installed since that date.) Run the free version of Malwarebytes (see tinyurl.com/y3ju6oov). There are also problems in Windows that can cause new System Restore points to vanish:

• Simple software errors. System Restore points are stored in a folder called "System Volume Information." If that folder is corrupted, new restore points won't be saved. To fix that folder, disable System Restore, then re-enable it (see tinyurl.com/yc4er5lk). That will erase the corrupt System Volume Information folder and create a new one.

• Flaws in the Windows file system or on the hard disk. Run the "Check Disk" feature of Windows, which is abbreviated as "Chkdsk" (see tinyurl.com/y436geqk). It will fix file system flaws, and if it finds bad spots on the disk, it will fix them or tell the PC to avoid them.

If Chkdsk reveals problems in Windows, you can make sure they get fixed by running the Windows "System File Checker" (abbreviated SFC), which replaces missing or damaged files (see tinyurl.com/y6cctzut).

• Problems you can work around. Try starting your PC in "Safe Mode" (see tinyurl.com/yytu3gfz). This starts Windows with a minimum amount of the operating system running, and that may allow you to work around a problem within the larger Windows program. For example, if a Windows flaw is preventing you from seeing the System Restore points you've created, those same restore points may be visible in Safe Mode.

Q: When I upgraded the operating system on my MacBook Air to Catalina version 10.15.6, it caused my Microsoft Word 2011 program to stop working. Will I now have to pay the subscription fee for Microsoft 365, the online version of Office, so that I can convert my Word files to Adobe PDF or Apple Pages files?

Doris Wickstrom, Minneapolis

A: Microsoft 365 isn't the answer. It could convert your Word files to PDF format, but not to Apple Pages format.

But you don't need to convert your Word documents to a different format, because the Pages program can do it for you. Start Pages, go to File and open the Word document you want to convert. Pages will open the Word document (no matter whether it uses the .doc or. docx suffix) and automatically convert it to Pages format.

When you have finished editing the document, Pages will normally store it in the Pages format. But the program can also store the document in the Word or PDF formats (for details, see tinyurl.com/yxv9jkaf).

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