We've noticed issues where the Windows RDP server stops responding to clipboard requests - this causes clipboard syncing to stop working in RDP sessions occasionally. The easiest way to get it working again is to log off the remote user and then log back on - this always fixes the issue. However, if you can't log off the existing session here is a faster / quicker solution contributed by a Jump Desktop user:
Solution to copy paste not working in Remote Desktop
I have seen that copy pasting and clipboard sharing may fail to work correctly at times. There may be a variety of reasons for this including mis configuration and incorrect settings. However, one of the common reasons I have seen is the rdpclip.exe going out of sync in the rdp sharing chain. If this is the reason for the copy paste not to work, the quick solution is to restart the rdpclip.exe program in the remote computer.
Here are the steps:
1. Kill the process rdpclip.exe using the task manager in the remote computer
2. Go to RUN command and start the application rdpclip.exe
Once the rdpclip.exe is relaunched, you should be able to copy paste using clipboard from the local computer to the remote computer. (If you are a novice Windows user, you can find detailed step by step instructions here (http://www.mywindowsclub.com/resources/5607-Copy-pasting-clipboard-not-working-Remote.aspx ).
However, if the copy pasting never worked for you in your RDP session, then this is not the solution. Instead, make sure you have done all the steps correctly, including enabling clipboard sharing as mentioned in the original article here.