On Windows I get the error message "Manager already installed and running" on Wireguard.

You have installed Wireguard for your Windows operating system as an administrator and you get the following error message:

"Manager already installed and running."

After reinstalling Wireguard, try restarting your operating system directly.
If this unfortunately did not help, please write to us at hotline@rhrk.uni-kl.de.
In Windows, the Wireguard icon no longer appears in the taskbar. What now?
Error message: "Unable to import configuration. The tunnel name is invalid 'wgtuk-.. (1)' ." What can I do?