KB45358: "Email Delivery Failed...Cannot connect to a socket... No more mail Exchange Servers to try" error message appears when sending an email subscription using MicroStrategy Distribution Services 9.x

SYMPTOM:
When sending an email subscription using Strategy Distribution Services 9.x, users may see error messages as below: 

[HOST:ALAN-PC][PID:6640][THR:4580][Distribution Service][Error] 
MSIDeliveryEngine::hDelivery(): Email Delivery Failed. Error string from 
ExecuteMultiProcess MNet::SocketImpl::Connect() - FAIL. Cannot connect to a 
socket: xxx.xxx.xxx.xxx:25, errno = 0 Connection refused Socket Error: 10061 
No more Mail Exchange Servers to try Unknown error . 
<Subscription 'xxx' (ID = xxx), Contact 'xxx' (ID = xxx) >

 
 
CAUSE:
Strategy Distribution Services 9.x does not support to delivery email against SMTP server which requires authentication.
 
ACTION:
Strategy Distribution Services 10.x supports SMTP authentication with TLS encryption.  Upgrade to the most recent Platform Release or Feature Release version to take advantage of the new functionality.

KB45358