While forming a fault-tolerant team, with an Intel Pro 100 Intelligent Server adapter, on your Window NT 4.0 server, you receive the subject message.
It has nothing to do with Windows NT Terminal Server.
The software found a Terminal Server sub-key at HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion.
Simply backup and delete the Terminal Server key, to allow your installation to proceed. When you are done, add the key back.
NOTE: Some program added the key, probably Microsoft Office.
NOTE: Windows NT 4.0 added the ability for 3rd party manufactures to support network adapter fault-tolerance in SP3.
see Q171415 - Network Adapter Fault Tolerance for Windows NT 4.0.