Hi,
This is a good and valid question; however, it truly has nothing to do with
Remote Operations Manager and is best posted in a RDP forum.
https://social.technet.microsoft.com/Forums/systemcenter/en-US/home?forum=winRDc
You could upload the screenshot to the OneDrive and post the link.
As far as I know, you can try to add the user to the Remote Desktop Users group in Computer Management.
Run > compmgmt.msc;
"Start",
» »
"Control Panel",
»
"Administrative Tools",
» »
"Computer Management"
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