Views:
Behavior:
While testing your SMTP connection, you receive the following error;
 
 "4.3.2 Service not available" 

Solution: 
This can occur when your DocuWare Server(s) are not given the correct permissions on the Exchange server. Please verify your DocuWare Server(s) are white listed on your mail servers.

KBA applicable for both Cloud and On-premise Organizations.
This article is valid for DocuWare versions: 7.3 7.4 7.5 7.6 7.7 7.8 7.9 | "4.3.2 Service not available"; SMTP