Unable To Print Within Network?

I have been having trouble printing from my laptop computer and desktop computer. I have installed and reinstalled the print drivers on both computers. Although odd, after removing the printer from printers and devices, it always reappears and has an exclamation mark on it. I have reset the home network router, the print server, and restarted multifunction printer devices several times. On occasion, after resetting the network, the printer will print something that was backlogged in my print que many sessions ago. To get a better picture of my current network, it's current set up is as follows: My home wireless router is a Dlink- DIR -655. I have the laptop and desktop connected to the wireless router via ethernet cable. The print server is a Dlink dpr-1260, connected to the printer via usb. The print server is connected to the wireless router via ethernet cable. The desktop is running windows vista and the laptop is running windows 7. I am able to successfully login to the print server through my network at its IP address. From there I run the print wizard and successfully download and install the print drivers. I click yes to confirm print test page. Soon thereafter, a message pops up saying "This program may not have installed correctly."

I am beginning to lose patience as this has been an ongoing problem for a few months now. I do not know where to begin or what to replace. It seems as though when I attempt to install or reconfigure a computer from the network, the printer and associated devices begin having issues. So once again I am running laptop windows 7 with service pack 1 64-bit; windows vista desktop; DIR-655; DPR-1260; and Brother MFC-8440.Everything is connected via ethernet. I am running avg antivirus software and comodo firewall on both computers.