Error installing Client for Microsoft networks

I cannot see workstation service in services list on bootup(OS::XP Pro).Upon searching various post,I found that Client for Microsoft networks should be installed to resolve it.
I checked network properties and found that it was not in the list.But,on trying to install it,I get error as “The service cannot be started, either because it is disabled or because it has no enabled devices associated with it”.

pls help me..I remember i changed my lan card a month ago,but it got detected and installed automatically by OS on next bootup of PC.

Any answers???I need resolution to it desperately