Three Perplexing Printer Problems
1. Printer? What printer?
When you select File -> Print, you should be able to choose your printer from the Printer pop-up menu in the dialog box. But what if your printer isn't listed in the pop-up menu at all? On rare occasions, for reasons often only known to the Mac gods, a printer will vanish from this menu, even though it was present the day before. One known instance when this can happen is after a user reinstalls or upgrades to a new version of OS X.
All you usually need to do is select File -> Print, click on the Printer pop-up menu, and then select Add Printer. This opens a window in which you should be able to find your printer. Simply select your printer and click on Add. You can also access the Add Printer window by clicking on the plus-sign (+) button in the Print & Fax system preference.
If your printer does not appear in the Add Printer window by default, you may need to select a different option from the window's toolbar. For example, for a Bluetooth-connected printer, click on the Bluetooth icon.
Tip: You can sometimes solve a variety of printing problems by deleting and re-adding your printer in the Add Printer window, even if you see it listed there correctly. (See "Remotely fixing the family printer" for a details.) To do this, first delete the printer--select its name in the Print & Fax system preference and then click on the minus-sign (-) button. Then re-add the printer as just described.
2. Errors when you try to add
Sometimes when you try to add a printer, you'll see this message: "An error occurred while trying to add the selected printer." What now? It's time to reset your printing system: Go to the Print & Fax system preference. Control-click on the Printers list. Then, in the contextual menu that appears, select Reset Printing System.
According to this Apple support article, this last-resort nuclear option will delete all printer queues and jobs, reset all printer settings to their default by deleting configuration files, and perform a permissions check on the /tmp directory. In other words, you'll have to set up all your printers again as you did when you first connected them to your Mac. With a bit of luck, however, your printing problems will disappear.
3. When all else fails
If nothing I've advised has solved your printing problem, give Fixamac's $30 Print Therapy a try. This program is chock-full of features. It will check and repair permissions settings for virtually every print-related file on your Mac, delete temporary cache and spool files from the /var/spool/cups directory, and restart the cupsd process. The last two items in this list refer to fixes to the CUPS (Common Unix Printing System) software that underlies all printing on a Mac. Any of these actions may jump-start a stalled printer.
Tip: Advanced users can tinker with CUPS directly, either via commands in Terminal (/Applications/Utilities) or via the CUPS Web interface (type the address http://127.0.0.1:631 into your browser's location bar).
When he isn't Twittering (@tedlandau), Macworld Senior Contributor Ted Landau is busy working on the third edition of Take Control of Your iPhone.