Barney could not print of a shared printer i.e Heathers HP laserjet 3150 which is configured for him to use. It prompted that the server could not verify the machine. On looking at the properties of the configured printer I managed to notice that Heather's machine was identified using her IP Address. That was the problem because though all the machines within the company have static IP Address fished out by the DHCP server but still every time the machine reboots the IP Address changes. Heather's machine had a different IP Address now and thats the reason Barney couldn't print of her machine.
I deleted the set printer and configured it again using Heather's computer name file://// Laserjet instead of file:////100.1.1.197/Heathers. In this case even if her system is rebooted and IP address changes the computer name would not.