Hi,
Thank you for posting your issue to Microsoft Q&A forum.
I think your issue should be caused by too old remote desktop client. Do you have any error message when the issue happened?
Please kindly check below two possible solutions to see if they can help to resolve your issue.
Because of a security error, the client could not connect to the Terminal server
Windows Server 2012 RDS and Windows Mobile: connection error
You can also check the discussions in below threads that described the similar issue as yours for more solutions.
Windows Sever 2012 RDS + Windows CE 5.0 Remote Desktop Client
WIndows CE 5 not connecting on a new server infrastructure 2012 R2 and wich version are supported?
Best regards,
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