We have created one RDP file for user RemoteApp Program, it's worked.
As before, I have got a testing and type wrong username into "user name" field. Now it always remember the "wrong username" when I re-login by RDP file
(Please see the attachment)
1. I must click "Detail" button
2. Waiting for a few seconds, and then wrong username message come out
3. Type the real username and passwrod again for each logon.
Once you edit it and connect it, it should remember the setting.