The part about the username/password appearing before the cert warning sounds wrong. I distinctly remember that all the RDP packets went inside the TLS connect

The part about the username/password appearing before the cert warning sounds wrong. I distinctly remember that all the RDP packets went inside the TLS connection. Perhaps they just delay the cert warning until after RDP has been started? I'm sorry but it's been 14 years and I've tried not to look at RDP in the interim. You may revoke my "expert" status. :D I'd guess that even with TLS enabled you're still vulnerable to MITM since hardly anyone is going to use certs that can actually be validated against a root.