This can happen if the folding@home software is installed twice, or if the software is conflicting with another process running.
You can check Task Manager to see what the other process is - open it up, go to the processes tab, click View - select columns, and check the box for PID.
See what process has a PID of 216.
There are ways around this, you can restart the client manually but it may cause problems. Better to try and resolve the conflict if possible.