Wireless printing stopped working. (10.8.2 / HP Officejet 6500)

I have a MacBook (MB5,1) currently running 10.8.2. My printer (HP Officejet 6500 Wireless) worked fine wirelessly from when it was first installed (Snow Leopard) thru Mountain Lion. About a week ago, the printer disappeared from my list of available printers and attempts to re-add it have failed. (Within the Print & Scan System Preferences, when I select the "+" to add a printer, it doesn't populate in the list of available printers to select)

I attempted reboot of the computer/printer/router, with no change. I also downloaded and installed the latest HP Printer drivers from Apple (https://support.apple.com/kb/DL907) then rebooted, with no change. I searched the forum and found several [somewhat] similar issues, but the suggested resolution from those that I found also produced no changes.

My wife's macbook (MBPro7,1) is currently still running 10.6.8, and still prints/scans fine (Same router and printer).

Any suggestions greatly appreciated. Thanks!

Have you tried connecting the printer up via USB to your MacBook then hit software update?

osxx said:

Have you tried connecting the printer up via USB to your MacBook then hit software update?

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I just did. Computer recognizes it via USB (it auto-populated into the 'Printers' list of the Print&Scan System Prefs) and via USB, it prints fine. Software Update while plugged in yields a "No Updates Available". Trying to add the printer subsequently (plugged or unplugged) displays no available wireless printers.

OS X 10.8 Mountain Lion: Installing and Using the Printer on a Mac with Mountain Lion HP Officejet 6500 Wireless All-in-One Printer - E709n | HP® Support

Aside from this have you re-started both your Mac and HP printer?

osxx said:

OS X 10.8 Mountain Lion: Installing and Using the Printer on a Mac with Mountain Lion HP Officejet 6500 Wireless All-in-One Printer - E709n | HP® Support

Aside from this have you re-started both your Mac and HP printer?

Click to expand...

Yes. I followed those directions and can print via USB but the printer still doesn't show up wirelessly. I have restarted the mac, printer, and my router as well.