The Vault Pro 2020 Add-in for Microsoft Office 365 apps for Excel and Word are being disabled as they load on a Windows 10 version 1909 workstation. Before version 1909 the add-ins launched normally. Also, the Outlook add-in works normally with version 1909.
Further, Excel cannot be closed after checking in a file into vault, after the add-in has been reloaded.
This was tested on a domain that loaded Microsoft OneDrive and SharePoint as well as Microsoft Azure Information Protection. The Excel 2016 was running from Office 365.
What was found to interfere with the Vault add-in was a Microsoft application called "Microsoft Azure Information Protection" inside Excel's Options.
Microsoft Excel Options (shown on a workstation in the Netherlands)
The confirmed solution was to uninstall "Microsoft Azure Information Protection" that appears in the Program and Features like this:
Once uninstalled, then Excel and Word were able to retain the Autodesk Vault Addin for Office 2016 and also check out, check in and close Excel normally.