HP PSC 1350xi prints only yellow, except test image

[Cambreaker]

I am using a HP PSC1350xi on Windows XP SP3. It has worked for several years, until yesterday. Now, all of a sudden, it will only print the yellow component of the "alignment" test page, nothing for normal print jobs, yet it will print its self-test butterfly image perfectly. The print cartridges are new and clean, and properly installed. I have uninstalled and reinstalled all the software and drivers, including downloading the latest from HP.com. Cartridge contacts are clean. I have followed every suggested fix I can find. I am at my wit's end, and I have no more time to waste. PLEASE HELP.

Have tried:
New cartridges (prints test image perfectly)
Clean cartridges (see above)
Clean contacts (see above)
Re-install all software and drivers from CD
Re-install all software and drivers from HP.com
Update all software from HP.com
Print directly to printer (as opposed to spooling)
Pound head repeatedly on wall
Pound head repeatedly on printer
Cry

 

[bigkel]

Have you downloaded the HP Printer diagnostic utility, here,s the link Let us know how you go. http://h10025.www1.hp.com/ewfrf/wc/documentSubCategory?tmp_rule=36029&tmp_task=solveCategory&cc=au&dlc=en&lang=en&lc=en&product=3742086

 

[Cambreaker]

Ah! I actually downloaded it yesterday and tried. It said it checked out OK, and proceeded to print a very blank test page to prove it. Because I will not turn down any advice at this point, I tried it again, with the same result.

 

[Cambreaker]

An additional note (and bump!) My wife suggested that, since this is a software issue, that I try using the printer's on-board Black or Color copy buttons, thus leaving the computer out of the loop. However, this prints blank as well.
Please help. I have a reasonable level of knowledge, so advanced repair instructions will not be lost on me.

EDIT:
Reinstalled again, this time making sure all HP peripheral programming was first removed, including director and other crap I don't need.
Tried different USB port.
Read HP.com's useless troubleshooting guide.

 

[Cambreaker]

Any ideas? Any other locations on the web I can seek advice for this thing?

 

[Cambreaker]

News: Tried a Windows Restore Point from long before the issue arose, no luck. Please help?

 

[Cambreaker]

Update: After the scanner has ceased communicating with the computer (the power light just blinks when I press the scan button), I tried another restore point further back. Now, HP Director and some of the other peripheral programs don't function. Any ideas at all are appreciated.