This is admittedly a simple one, and something you are likely not going to run into on a daily basis. Today I had an issue with the clipboard whereby a new Ctrl-C would not overwrite the existing clipboard contents (even multiple attempts to overwrite the clipboard would fail). I have no idea why this happened – I only know I was jumping in and out of RDP, perhaps something went wrong in there – but the fix is very easy:

  1. Open cmd
  2. Type echo on | clip

(echo off | clip would also work).

Why does this work? echo, with the on and off parameters, is a command that does not print anything to the standard output; clip is a command line util that, from its official description (clip /?),

Redirects output of command line tools to the Windows clipboard.

Consequently, if you pipe an empty output to clip, you are effectively piping an empty output to the Windows clipboard, erasing its previous content.