Trojan Gen 2 and Trojan.zeroaccess.c removal

My toshiba windows7 64bit laptop has symantec endpoint protection, and it's reporting these infections in about a dozen files in two different locations, pretty much every time it scans.  Some of the files it is able to delete/quarantine, but some report "Access Denied".  I've read other similar topics on here, with warnings about not trying anything yourself,  and so I have not tried to do anything myself or run any other tools to start working on this.  If someone can walk me through the process it would be greatly appreciated.