Q: I like to use the "shuffle" option for music on my iPhone and photos on my digital picture frame. But I've noticed that I'm hearing the same songs and seeing the same photos more often than I should if they were really being played randomly. This seems to defeat the purpose of the "shuffle" command. Is there anything I can do about this?

Kathryn Heller, Colorado Springs, Colo.

A: I suspect that the "shuffle" behavior you are hearing and seeing really is random. It's just not in the way you expect.

Why? Just as cards are put into a random order when the deck is thoroughly shuffled, the playing order of your songs or photos becomes random after you "shuffle" them.

But to get a truly random experience in which each card, song or photo is "played" only once, you must go through the entire deck of cards, music library or photo collection in one sitting.

Most people have such large song or photo collections that it would take too long to play them all in one go.

Here's the catch: The next time the iPhone or digital picture frame is put on shuffle, it doesn't resume playing the songs or photos in the same sequence as before. The shuffle command has created an entirely new random playing order that has no relationship to the previous one. As a result, songs or photos that played in the previous shuffle may soon reappear in the new one. Alas, there's no fix for this. While you can "pause" an individual song or photo and return to it later, you can't pause a shuffle sequence. Every time you choose "shuffle," it's a brand-new deal.

Q: I turned off automatic ­Windows 7 updates years ago, and I've been safe despite not getting security updates. Why can't I continue to be safe after security updates are discontinued Jan. 14?

Janice Oakley, Sagamore Hills, Ohio

A: The threat is much worse now. By some estimates, there are nearly 200 million PCs still running Windows 7. That's a big target for hackers. If a new Windows 7 security flaw is discovered after updates cease, it could be a disaster for lots of people.

Q: I used Microsoft Office for Mac for years. After I switched to the online Office 365, hundreds of my old documents and spreadsheets were missing. What can I do?

Richard Palazzo, Davenport, Fla.

A: I suspect it's a file format problem. If so, you can get your old files back.

If you were using Office 2004 for Mac, it stored your files using old file suffixes (for example, ".doc" for Word documents, or ". xls" for Excel spreadsheets.) Newer versions of Office replaced ".doc" with ". docx" and ". xls" with ". xlsx". By default, new Word and Excel programs look for the new file formats and ignore the old ones, which makes it seem as if the old files are missing.

Try this fix. When you begin to open a Word or Excel file, you'll see a box with a list of available files. In either program, you'll see a drop-down menu to the lower right of the list of files. In both Word and Excel, use that drop-down menu to choose "all files" instead of "Word documents" or "Excel files." That will cause all your old files to reappear.

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