8.0-999.0 isn't actually a valid version. Check your version by opening Studio and going to Help >> About Pega Robotics Studio.
You will need to have selected Office 2016 during install of Pega Robotics. You can verify that you have the correct version selected by going to your %appdata%/openspan folder and checking the RuntimeConfig (and StudioConfig) for the OfficeVersion key. It should look like this:
<add key="OfficeVersion" value="2016" />
If this is correct, reset your toolbox and add the connectors back in (if they don't do it by default). Then add your connector to the project and try again.
Great. Thank you. Ok, the error is occurring because we do not detect the registry values that you would normally find with Office installations. We're looking for the office value here : ...SOFTWARE\Microsoft\Office\2016.
Can you check? Or additionally find where the office registry value is set?