Printing pauses on Shared Hp Printer

Hi All

Hopefully Ive got this in the right place.

I work as a school tech in oxfordshire and although have enough mac knowledge to face most of the problems I come acorss this one has me stumped and Im after some help.

We have 8 iMacs on Snow Leopard in the photography department which are connected together either through the inbuilt wireless or ethernet cables. 1 Mac has 2 printers connected to it which are then shared out to the rest. One is a Canon ix5000 and the other an HP officejet 8000. Both printers work fine from the original machine, however the HP yesterday started to pause printing from all shared machines.

Whenever an item is sent to print the printer automatically pauses. Trying to resume the printing occasionally brings up the error message "client-error-not-authorised", however sometimes just nothing happens! The Canon still prints fine from all machines and as Ive said this is only occuring on the machines the printer is shared too. It prints fine on the machine it is connected to.

I have tried removing and adding the printer and also running the repair disc permissions on all machines and adding and removing the printer again after that didnt work! Googling the error brings up reports of a security update from 2008 causing problems however I have not run any updates recently and 2008 is a while back!

Any suggestions are welcome, we have exams starting next week so this is a bad time for it to go wrong!

Thanks

Steve

Sorry for the bump. This is still not fixed, im out of ideas and the exams start on Wednesday!