We have RDS installed in Windows 2008 R2 Standard edition and configured RDS Web, RDS Gateway, RemoteAPP, ADS, DNS in the same server which is in DMZ and we have opened the port 443 only for the clients and enabled the self signed certificate. We have tested this setup with various windows 7 ( 32/64 bits and IE9/IE10) machines, everything works fine. But few clients are getting the below error.
RemoteApp Disconnected
This computer can't connect to the remote computer.
The two computers couldn't connect in the amount of time allotted. Try connecting again. If the problem continues, contact your network administrator or technical support.
Please suggest a way forward. 3 users are able to connect from windows 7 (IE10) PC, but 3 users are getting the above error they are also having windows 7 (IE10) PC.