Unable to communicated with Terminal Server

Hello all there,

i have installed Windows Terminal Service on Windows Server 2003. Domain Controller is installed on other computer. I want to communicate Terminal Server With Domain Controller But Unable to communicate, i am even unable to ping Terminal Server. While Terminal Server is able to ping all the system in the Network. There is no Antivirus installed on Terminal Server, So what may be problem ???
Is it Necessary to Installed Terminal Server in Domain, Can we install it without domain ???

Kindly Guide...

Thanks

Jazaib Hussain