There is a clipboard bug in the latest RDP release which causes the remote windows clipboard to lock with "Windows cannot open clipboard" message (depending on the software you're copying from the message can differ to Cannot empty clipboard, Cannot copy to clipboard, etc.) . There is little known at the moment about the steps to reproduce it but the following conditions must coincide:
* the remote linux system got to support native encodings (UTF clipboard buffer at the remote side must contain something in a none-latin, national locale, I have this bug while working with RU locale)
* you have tp copy text to the clipboard at the windows side using right mouse button
* the remote system should run XP with the latest updates
Reconnecting to the remote host won't solve the clipboard problem. When copying windows displays error and you're unable to use windows clipboard.
Logging locally to the affected computer will solve the problem with clipboard - it will resume to work.