This topic describes the troubleshooting steps in the case of establishing a session to a remote host reacts differently in Remote Desktop Manager than when you are using mstsc.exe.
Our Embedded display mode uses the Microsoft ActiveX and offers the most customization options, but is inherently different than using mstsc.exe. When wanting to ensure the issue is really in Remote Desktop Manager vs being an issue with the ActiveX, the procedure is to try to replicate the scenario with Microsoft's RDCMan. You can obtain that tool from http://www.microsoft.com/en-ca/download/details.aspx?id=44989. Simply install it, create sessions like you have in Remote Desktop Manager, then open them concurrently or in repetition to replicate the issue you think lies in Remote Desktop Manager.
When you choose to use the External display mode, Remote Desktop Manager will in fact create a temporary RDP file and call mstsc.exe with the file as a parameter. It can be beneficial to grab that file while it exists and to compare it with one created using mstsc.exe.
1.Create or duplicate a session that you want to diagnose, set the display mode to External.
2.Launch that session
3.The file will be deleted when you close Remote Desktop Manager, you need to copy it before then.
4.Open %TMP%\RDM, copy your file in another folder
5.Open the file in your editor of choice and compare it to a file created using mstsc.exe
We have isolated the issue by changing your RDP engine version to RDP 6.0 or 7.0 in File -> Options -> Types -> RDP