Tidserv Activity 2 is a Norton Antivirus`s signature which indicates that your computer is infected with a Tidserv trojan. The trojan also known as Backdoor.Tidserv [PCTools], Backdoor.Tidserv.I!inf [Symantec], Rootkit.Win32.TDSS.y [Kaspersky Lab], Patched-SYSFile.a [McAfee], Mal/TDSSRt-A [Sophos], Virus:Win32/Alureon.F [Microsoft].