Good morning dear ChristyZhang-MSFT :)
Many thanks you for your effort and your reply. We use Group policy objects in an Active Directory environment SchemaVersion 87 with Exchange Schema Version 15333. This Outlook GPO is assigned to an organizational unit within the Active Directory. The GPO is active and enforced and is distritbuted to all objects within the mentioned OU.
I checked twice your mentioned Microsoft document, but did not found any difference to my configuration.
The hash of the DLL can get with the Powershell utility "Get-FileHash":
- Get-FileHash
[-Path] <String[]>
[[-Algorithm] <String>]
[<CommonParameters>]
I used the SHA256 and the MD5 Hash of the DLL as well to check if there is any difference but it doesn't seem so.
But meanwhile I configured the following settings to "Prompt users based on their computer security"
- Configure Outlook object model prompt when accessing an address book
- Configure Outlook object model prompt when reading address information
- Configure Outlook object model prompt when sending mail
...and it seems to work now.
But I'm still unsure if this is the appropriate setting for this configuration or if I just lowered down the security level.
I guess I need some more research to find a resilient answer.
But again, many thanks for your help!
Sincerly
Anonymus