My computer does not connect properly to my printer/communication error/cannot open port.

a.      Verify IP address
b.      Confirm you are using a static IP address
c.      Confirm IP address in the RIP
d.      Check cables for connectivity and that you are using the correct cable type – i.e. crossover for workstation directly to printer
Cross-Over Cable
http://www.hardwaresecrets.com/article/426/2
e.      Reseat network card