Port 135 is essential to the functionality of Active Directory and Microsoft Exchange mail servers, among other things.

epmap stands for End Point Mapper, and represents that your computer has established a listening port for another process.

Some of this is benign. See the following to determine who and what is using the RPC service: http://petri.co.il/quickly_find_local_open_ports.htm

1. Make sure you have a firewall. The native XP ICF firewall is sufficient.

2. Make sure you have all the latest MS security patches installed. Visit the MS Windows Update site to check your system.

Found on some sizites.