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bit of a newbie to this, good at tinkering and following instructions, but by no means technical.
I'm getting the following error in the AppCenter
W: The repository 'http://ppa.launchpad.net/versable/elementary-update/ubuntu xenial Release' does not have a Release file.W: Data from such a repository can't be authenticated and is therefore potentially dangerous to use. W: See apt-secure(8) manpage for repository creation and user configuration details
Any advice gratefully received.