tcp.h definition, relationships, removal:

This is a part of a malicious parasite that violates user privacy and damages the compromised system. The tcp.h file can be used for different purposes depending on the related parasite's type, functionality and carried payload. Although tcp.h may not take any malicious actions by itself, it ensures that a parasite is working properly and therefore needs to be removed. DO NOT open, execute or edit tcp.h!
The tcp.h file is installed and used by sniffer ADM Sniffer.
In some cases a presence of tcp.h does not mean that your system is infected. The file may actually belong to some fully legitimate applications and therefore must stay intact. If you are in doubt, please scan the tcp.h file using you regular spyware remover or antivirus program.