Serious problems might occur if you modify the registry incorrectly by using Registry Editor or by using another method. These problems might require that you reinstall the operating system. Microsoft cannot guarantee that these problems can be solved. Modify the registry at your own risk.
This alert occurs when you have the following data configured in the Windows Registry. This configuration causes Outlook to automatically deny requests from any programs that attempt to access Outlook data.
Outlook 2010 and later versions:
In the above registry key path, x.0 corresponds to your version of Outlook (17.0 = Outlook 2019, 16.0 = Outlook 2016, 15.0 = Outlook 2013, 14.0 = Outlook 2010).
The available value data for these registry values is listed below.
1: Prompt user
2: Automatically approve
The above registry data in the Policies hive may be controlled by a Group Policy. The Policy may need to be modified to permanently modify these settings.