OfficeJet 7500 won't print via WiFi anymore even though pings are successful

Question

This is a new OfficeJet 7500 All-in-One that I have been trying to get set up over the weekend but have run into problems.
First here is the system data:
From the EWS printer information page:
Product name: OfficeJet 7500 E910
Product Model Number: C9309A
Firmware Version: EMP1FN1126AR
From the Wireless Network Test Report printed out Jan 23 2012 9:07 AM:
No problems found. Congratulations on the successful setup of your wireless printer.
Diagnostics Summary
Wireless On: Pass
Wireless Working: Pass
Network Name (SSID) Found: Pass
Security: Pass
Printer Settings Consistent with Wireless Router Settings: Pass
No Filtering: Pass
Connected: Pass
Signal Quality: Excellent
Other networks detected matching your network name (SSID): No
Wireless Networks Detected: 10
Disconnect count total: 32
Disconnect count (last hour): 0
Disconnect count (last 24 hours): 5
Channel: 1
Configuration Summary
[Shows correct network name]
Hardware Address (MAC): [will report if it is needed]
IP Address: [It is static and working--pings are successful]
Configuration Source: Manual
Communication Mode: Infrastructure
Authentication Type: WPA-PSK
Encryption: Automatic (AES or TKIP)
The Network Configuration Report concurs with the info above and also shows that the nearest three 802.11 networks are at least five channels away from mine, but the fourth nearest one (with a signal value of -83: mine is -21) is the same as mine (channel 1).
The computer I'm using is a MacBook running OS X 10.6.8
Things I have done:
Confirmed that MAC filtering is disabled.
Tried to figure out the router firewall. As far as I know, it is ordinary, and there are no other firewalls installed anywhere. I don't know how to determine if this is a firewall issue.
Rebooted everything many times, being sure to turn the router back on before the printer.
Uninstalled and reinstalled via USB cable the full driver package downloaded from the HP website.
Assigned the printer a static IP address.
Changed the channel in the router.
Disabled and re-enabled Bonjour.
Searched the forums.
The problem I'm having is that when the print queue says that the printer is ready and I send a print job, it looks for the printer a few moments and then says that the printer is offline. Nor can I print from my iPad or iPhone (although at first I could). At first I discovered a workaround by turning off the WiFi radio on the printer and then turning it back on, and for a very short time (a minute or two) after that, the printer would show up in the queue as "connected" and the job would print. This workaround no longer works. I don't know if any of the changes I made correspond with that.
Rebooting the printer is another workaround I discovered that continues to work, but only for a few moments. If I send a print job right away or a job is waiting in the queue, it will print it right after I turn the printer back on, but then everything goes haywire again. Rebooting the printer with the HP Utility window open produces alternating popup windows reporting attempts to connect to the printer and then reporting that it can't connect. They alternate at a sort of frenzied pace for a minute or so and then the "can't connect" popup stays. After a while, if the HP Utility window stays open, the frenzied popups return .The rest of the time the HP Utility says the printer is not available, even when pings are successful, even when I can access the EWS, and even when the printer is actually printing a job.
I can't seem to figure out what Bonjour is or what it does despite reading about it on the Apple site. Here is how it has been behaving: When I reboot the printer it shows up on the Bonjour list, but when I click on it there, it disappears and a Safari popup says that it can't find that printer server. Disabling Bonjour seemed to change nothing, and re-enabling it seemed to change nothing either.
So that's the data. Thanks in advance to whoever can shed some light.

Answer 1

Hello Sindigirl,
Thanks for the detailed information. And from that information, I can allready see that we are dealing with a intermittent bonjour connection. Bonjour is the protocol that all apple systems work with, they have the option to automatically detect new devices in your network.
From what I can see, you did about everything humanly possible to resolve the issue. If however the router that you used always has worked fine and did not cause any network issue's whatsoever, the giving the router a powercycle should often resolve the issue if it is a bonjour compatible router, if possible, please report the manufactuar of the model that you have and its model number.
For a workaround so that you can at least print you can use the following steps. Please note however, that scanning will not work with the workaround, since this is bonjour dependant.
[1] Go to Apple/sys. pref./Printer and faxing.
[2] Click on the[+] to add a printer
[3] Instead of [Default] in the upper tab, select [IP].
[4] Switch LPD (line printer deamon) to HP Jet Direct Socket.
[5] Fill in the printer IP adress at the the Option [IP]
[6] Leave the printing queue blanc
[7] Rename the printer [Should have the IP adress as name at the moment]
[8] Leave location blanc aswell
[9] Select [Add printer software] If a list pops up, the use the filter to lookup the 7500 driver, if found or allready reported then click add printer.
You can now print without any issue via direct IP printing. Please let us now what router brand and model you got.
Sorry for any typo's.
Kind regards,
van Baardewijk