HP CLJ 3600 and OJ 4215 NOT working tho supported--help pls!

Question

Andrew and all: (this is a repeat post first posted w/o any responses, on 10/5)
I travel betw. three offices; have these WORKING printers/drivers on my MBP13 w/Snow Leopard 10.6.1 onboard: HP LJ P1006: latest one, works FINE (thank goodness)
HP 4L: CUPS+Gutenprint v 5.2.4
(and a Canon MP 530 with driver version 10.19.0.0 working perfectly...the only one I have that did NOT experience a problem after installing Snow Leop)
*These HP printers, supported in Snow Leopard (per HP/Apple posts) have problems:*
HP CLJ3600n (direct connect with USB): message: CANNOT ESTABLISH TWO WAY COMUNICATION WITH THIS DEVICE; please check that your printer is connected and try again.
Intervention Attempted: Turn off printer and then on after a minute; reboot MBP. No change--still same error msg.
Printer works with a Windows XP PC when it was hooked up together on a manual A/B switch; works when directly connected via USB or when connected thru A/B to printer.
MBP does NOT work under ANY connection scenario. (Sharing is turned OFF).
HELP?
*HP 4215 Office jet.*
This is now at same location as the P1006 (that works fine): First problem,solved: after adding the printer, got msg that only part of the software was downloaded and printer would likely not work.
Downloaded again the latest HP drivers via apple Support; then reinstalled 4215--this time, NO MSG about partial download.
DID get a test page to print from within the driver utility.
WILL NOT print a page from any other app (ie, Word, Safari, etc.)
HELP!
In sum: I most need the CLJ3600n to print because it's the only printer I have easy access to at that office.
My MBP IS NOT connectable to the network at the worksite where the CLJ3600 is...am trying to ?simply? connected directly with USB cable or through manual A/B switch.
I would ALSO like the OJ 4215 to work bec. I'd like to have color option at home office.
Not for nothin', but why no problem with Canon and mucho problems with HPs?
Andrew and anyone else, please troubleshoot and let me know what to do! Thank you!
At end of printing rope in NJ:
Howard
MacBook Pro 13 Mac OS X (10.6.1) All mentioned printers worked with this Mac before loading Snow Leopard

Answer 1

NJpsychout,
Lets see if I can tackle your problems. First, let me state that we are going to go for a clean state and then re-install things. And all of this information is covered in the FAQ thread at some point. So with that being said, lets get started:
1) If any device is currently connected via USB, disconnect it.
2) Go to the Print & Fax control panel, right click on your printer (or in the empty printer list) and select "Reset printing system..." (this will remove all printer queues from your system).
3) If you have the HP Uninstaller in /Applications/Hewlett-Packard run it. When you get to the Uninstall screen, press Shift-Control-Command-Option while you click the Uninstall button. Click yes to the scary warning message.
If you no longer Have HP Uninstaller laying around the following steps will clean things up. Perform them even if you ran the HP Uninstaller.
4) Delete all the files that start with "hp" in /System/Library/Extensions (this is where one of your problems is).
5) Delete /Library/Printers/hp if it still exists (this is just for good measure).
6) To be really thorough, delete anything that starts with HP from /Library/Printers/PPDs/Contents/Resources. Since you also have a Canon, do not delete the whole folder.
7) Restart your machine, or better yet shutdown and wait a minute.
8) Install the full HP Installer (version 2.2). If you need it you can grab it [here|http://support.apple.com/kb/DL907].
9) Start adding the Printer Queues back.
10) If you disconnected a USB printer, don't forget to add it back.
You will not have Scan or Fax capabilities from the OfficeJet 4215, but we are working on adding and In-OS Scan driver for it. At this point you should be able to use HP drivers for everything except your Canon printer of course and the 4L which you'll still need the gutenprint drivers for.
If you're still having trouble at this point, post back what problems you are having and we'll try working through them. Oh, and you had one Canon printer and 4 HP printers. The chances of an upgrade issue are stronger the more devices you have. And the installation process in Snow Leopard is out of my hands.
Just trying to help.
Andrew