You *might* have migrated to Outlook New which does not support COM?
There is a registry entry you can add to stop New taking over, after why would you, if you have code like I have to send emails from Access for example.
As for CDO Colin has a test app you can use to test your connection. However as you must be aware CDO is just for sending?
https://isladogs.co.uk/email-tester/index.html