OK - no volunteers from HP Tech Support. I'll do this myself.
If you're having this problem - and getting frustrated as I was - here's what I finally did to solve the problem. All works well now.
Go to this HP Support web site:
http://h10025.www1.hp.com/ewfrf/wc/softwareDownloadIndex?cc=us&lc=en&softwareitem=mp-129932-1
1. Download HP's "Print and Scan Doctor".
2. Save the file (HPPsdr.EXE) to your downloads folder.
3. Close all open windows and applications that may be running.
4. Launch the HPPsdr.exe program from your Downloads folder.
5. When the program statrs, select PRINT (unless you're having Scan issues, then select "Scan")
6. Let the wizard do it's thing. It will let you know when it finds a promlem, and will automatically fix it.
My problem turned out to be files stuck in the print que that wouldn't delete. For some reason, this was causing the printer to show as "Offline" when it really wasn't. The Print and Scan Doctor resolved the print que issue - cleaned it out - now everything is working fine. You may have a different issue, but the Print and Scan Doctor should identify and repair them.
** This program is for Windows 7, 8 and 8.1 only. Win XP needs a diferent troubleshooter. **
Hope this helps..