Sometime when working locally I get that error when my database is unreachable / connections full.
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Anyone with issue please check your Joomla version under Site/System Information and make sure it's the version below or newer.
I think you might have installed the 2.5 version instead of the 3.0 version try uninstalling your current installation (Note: Just uninstall the component and it will take care of the other parts of the extension).
Did you get an alert letting you know that your device’s time zone is set incorrectly?