Vista - Share a printer

I connected a new HP officejet to the network. After much tinkering, I got it to work as a share among two vista PC's. Somehow, it no longer works 3 days later. (windows updates have been downloaded, that is all)

Both computers have:
Windows Vista 32, the other 64 bit
Windows firewall disabled
AVG firewall disabled
Identical user name and password (sheryl, an administrator)
file and print sharing is turned on
workgroup name: Workgroup

the ports for all of vista's sharing purposes have been opened on all disabled firewalls, just to be safe. (gotten from MS knowledgebase). Firewalls re-enabled, changes nothing.

Both PC's, router and printer have been rebooted.

The connections are secure.

I view 'Network' and find PC-2.
I click PC-2's icon and it asks for log-on information. I enter Sheryl and her password. PC-1\Sheryl and PC-2\Sheryl Dont work. (cannot log on, check user/pass, error doesnt mention syntax errors). Passwords and user name is identical on both computers.

Again, nothing has changed but windows updates. Nobody knows how to access the router, so there wasnt a change concerning the router's ports. The printer cannot function anymore, even though it is present as default printer in PC-2. Print monitor believes printer is jammed at all times, even when its turned off and works for PC-1. PC-2 simply can no longer access pc-1, as seen in the network window, access is denied.

Any ideas guys?