I have a SBS 2011 server. Users have started getting a delivery delayed message overnight.
The are sending via SMTP.DOMAIN.COM (DOMAIN is there domain obviously). But it is coming up saying Last Error is
"451 4.4.0 Primary Target IP address responded with "451 5.7.3 Require basic authentication.
This is odd as no setting have changed and it is setup to use basic authentication from the day it was installed.
When I try to see what is in the queue I get
"The remote pipline has been stopped. it was running command 'get-message - ResultSize '1000'- ReturnPageInfo $true - server 'SERVERNAME.DOMAIN.local; - Sort Order '-From Address' - SearchForward $true - BookmarkObject $null - BookmarkIndex '-1' - IncludeBookmark $false"
Which I have never seen before.
I have tried moving them to a new smtp details on a completely different server which another SBS 2011 server I have is using fire with the same error occurring so I don't think its the external SMTP service.