Latest Outlook Add-In version cannot be installed

When updating the MS Outlook Add-In, it can be that the newest version is installed without a problem, but the Add-In cannot be seen or used, and the old icon is still displayed.

The old install path is not accepted by Outlook.

Enter a new file path to install the Add-In (for example: C:\Programme\Reddoxx_2028).
The old REDDOXX icon needs to be manually deleted (Outlook -> Tools -> Customize -> select the Toolbars tab -> deactivate the REDDOXX toolbar)