Connection problem for second agent on same machine.

Hi,
I followed the instruction on http://confluence.jetbrains.com/display/TCD8/Setting+up+and+Running+Additional+Build+Agents to add the second agend. Now the second agent is visible on the agent tab. BUT in my build configuration I access a network drive and this access is somehow not allowed. Agent No. 1 can access the network drive but agent No. 2 is not allowed. The windows command "net use" failed.
How can I fix this problem?

Thanks for any help!