If you have Advanced System Care installed in your system than check the settings for Smart Ram listed under Toolbox and make sure the box for Clean Clipboard is unchecked. If the box is checked this will not allow any data to remain on the clipboard for copy and pasting operations. Alternatively you can try the below steps:
Start > Run (Type services.msc) and press OK
Check for clipboard and ensure the service is started under listed, if it is there, restart service by right clicking and then re-try copy and paste.