Q: wireless printer doesn't stay connected

Should be in Mac OS X area...

Also look at the MORE LIKE THIS on the right.

OS X Mountain Lion and OS X Lion systems will have the necessary printing software already installed, or will automatically download and install software when the printer is connected or configured. Do not install software that came with the printer as it may be out of date, and do not connect the printer to your Mac yet. Follow the instructions that came with the printer to unpack, install ink or toner, and insert paper.  Finally, use the instructions in this article to connect the printer to your Mac.

Make sure the printer model is listed in Printer and scanner software, which is a comprehensive list of all printer models that have compatible software for OS X Mountain Lion and OS X Lion.

How to add a printer

Start a print job on the Mac and manage its options

Generate and manage PDFs

Manage the printer queue and printer dock icon

Share the printer queue

Mac OS Printing/Fax (any version), OS X Lion, OS X Mountain Lion

http://www.apple.com/support/osx/

printing in OS X Mountain Lion

http://support.apple.com/kb/HT4670

If it doesn't work, reset the printing system:

http://support.apple.com/kb/HT1341

then add another print queue manually.

Also, check for a software update for your Lexmark printer.

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factory reset to the printer.

use google to find how to made the hardware reset of the rught model of your printer.

(special attention there are 3 kind of hard reset)

1. just clears ram of the printer and does't resets the config settings (you will need this one)

2. resets the configuration and the ram.

3. resets everything and the firmware and other hiden stuff (DO NOT DO THIS ONE)

cheers