Sim, acabei de fazer isso não muito tempo atrás.
Você precisa alterar algumas configurações no RDS, excluir algumas chaves do Registro e reinicializar o servidor para reconstruir os certificados com um nível de criptografia menor.
Veja aqui um passo a passo completo: link
Vou incluir as partes mais relevantes abaixo, caso o post do blog acima já desapareça:
RD License Server Activation Connection Method
To fix that and get compatible certificates re-activate the RD Licensing Server using the Web method. In RD Licensing Manager right-click the server name and select Properties. Change the Connection Method to “Web Browser”. Close Properties with OK and again right click the server and then Advanced-Reactivate. Follow the process to reactivate the server using the web browser.
After reactivation delete the following registry keys and reboot the server!
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Terminal Server\RCM
- Certificate
- X509 Certificate
- X509 Certificate ID
- X509 Certificate2
These registry keys will rebuild with lower security after reboot (see also [14]).
And, surprise, after reboot Remote Desktop Mobile (Windows CE5, Windows Mobile 6.x and Windows Embedded Handheld 6.5.3) can connect!