Mac will not see network drives!

A friend of mine was trying to fix a Mac tower for a small business, and determined that the PRAM needed to be replaced. After replacing it, the original problem was resolved, but the icons were scrambled, some settings were lost, and now it doesn't seem to see all the drives on the network.

If have fixed most of the issues, but the ones that remain all have the network in common. The small business is running a Samba and the network has been cobbled together over time.

Any suggestions? Is there a way to better access or utilize the network?