The Office Business Application for 2019 is accessed from the OnBase tab in the Microsoft Office application:
If the OnBase tab is not available, the Office Business Application for 2019 is not installed. If you have been provided with a URL or UNC path to the installation package, click the path to install Office Business Application for 2019. When the installation is confirmed, click Close and launch a Microsoft Office application to access the OnBase tab.
When the installation package is modified by your system administrator, you are prompted to install a new version of Office Business Application for 2019 after opening a Microsoft Office application.
If you have not been provided with a URL or UNC path, contact your system administrator.