Hello how are you?
Welcome to the Microsoft Community!
My name is Marcelo C., I am an independent consultant, I am here to help you in the best possible way.
Restart Windows Explorer
This will close all open applications and windows. Please save all work before proceeding with this solution.
Step 1: Start Task Manager again and find Windows Explorer under the Processes tab.
Step 2: Right-click and select the Restart option.
Reset the remote desktop clipboard process with administrator rights
On Windows, the Remote Clipboard process runs with the file name rdpclip.exe whenever Windows starts up.
Step 1: Press Ctrl + Shift + Esc on your keyboard to launch Task Manager and look for rdpclip.exe in the Details tab.
Step 2: Can't find it? Click File > Run New Task and type rdpclip.exe and select the "Create this task with administrative privileges" box. Press Enter.
Step 3: Restart your computer and check whether you can copy and paste in Windows 10 or not.
I hope the information above helps. Please let me know how it goes.
Have a nice day and stay safe.
Marcelo de C.