I am evaluating the free Remote Utilities for our departments use before buying the Pro version. I have installed Remote Utilities Server version 18.104.22.168  on a VMWare machine running Windows Server 2012 R2.
I found I could not run the Administration program again after I had closed it using the X button in the upper right corner. I found the cause to be the process "Remote Utilities - Server Admin Console (32 bit)" running in the task manager. If I kill that process I can run Administration again. In addition, the process does not show in the task manager until I close the app using the X button. I later found that closing the app using File >> Exit does not leave the process running and I can launch the app again.
Initially, I was thinking this may be an interaction with VMWare, but the difference between closing with the X button and using File >> Exit seems to indicate a bug in the software.
PLease note that it's expected behavior for both RU Server and Viewer not to fully exit when clicking the "X" button - in order to fully close the program and stop its respective processes, you need to close it via the File -> Exit menu command.
As for the administration program that can't be launched while RU Server is running - could you please specify the exact program? Do you mean Windows PowerShell, Remote Server Administration Tools or something else?
The Administration program is the one listed under "Remote Utilities Server" in the windows start app area. The program path is "c:\Program Files (x86)\Remote Utilities - Server\InternetIdAdmin.exe". I think you refer to it as Remote Server Administration Tools.
I was taught the "X" button and File -> Exit menu command should call the same routine and behave the same.
Why would the administration program want to be left running in memory at all when the program is closed?