Maybe this one offers some clues? Although if they are shutting down basic auth the time may have come
https://docs.microsoft.com/en-us/Exchange/mail-flow-best-practices/how-to-se...
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rk
From: ProfoxTech profoxtech-bounces@leafe.com On Behalf Of Ted Roche Sent: Wednesday, June 15, 2022 4:31 PM To: profoxtech@leafe.com Subject: Legacy app using wwipstuff.dll fails sending Office365 email
Hi, folks:
An ancient legacy app (soon to be mothballed) has been using wwipstuff.dll to send email through outlook.com since at least 2013 or so.
Once in a blue moon we've needed to tweak parameters but nothing for around 5 years.
I used BLAT to debug and get all the parameters set up correctly. Today, trying to get t to work, I get the error:
<<<getline<<< 354 Start mail input; end with <CRLF>.<CRLF> <<<getline<<< 550 5.7.64 TenantAttribution; Relay Access Denied [BN1NAM02FT037.eop-nam02.prod.protection.outlook.com] Message not accepted by server
putline>
This looks like some new requirement by outlook. A quick web search yields:
https://docs.microsoft.com/en-us/exchange/troubleshoot/email-delivery/relay-...https://protect-us.mimecast.com/s/aMqOC4xkqzTEqRLhMsDtW?domain=docs.microsoft.com
which talks about using certificates (doubtful) or a fallback IP address mode, which I don't remember having to walk them through before.
Anybody ran into this and know a quick fix?
[excessive quoting removed by server]