This article briefly explains why internet sessions cannot be used in standalone versions of DameWare Remote Support or for centralized versions of DameWare Mini Remote Control.
Refer to Limitations to Internet Sessions. Internet sessions are part of the Centralized version of DameWare Remote Support. If you have the standalone version of DRS or if you have the Centralized version of DameWare Mini Remote Control, you cannot use Internet Sessions.
If you do have the Centralized version of DRS, check the Internet Session Troubleshooting Guide.