OpenText Exstream SMTP Error with Office365: ssl3_get_record:wrong version number

Marius 3B · 2025-07-29T12:49:55+00:00

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Hi everyone,

I'm currently configuring OpenText Exstream to send emails via Office365 SMTP. Here's my setup:

SMTP server: smtp.office365.com
Port: 587
Authentication: Username and password provided in the TCP configuration
Security: TLS 1.2
Authentication type: Anonymous
Certificate: None specified

When I test the connection, I get the following error:

SMTP server: error:1408F10B:SSL routines:ssl3_get_record:wrong version number

From what I understand, this might be related to how TLS is being negotiated. Since port 587 expects a plain connection followed by a STARTTLS command, could it be that Exstream is trying to initiate TLS immediately instead?

Also, is it correct to use "Anonymous" authentication when credentials are provided?

Has anyone successfully configured OpenText Exstream with Office365 SMTP? Any advice or working configuration examples would be greatly appreciated.

Thanks in advance!

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Comments

be_informed1

Hello,

i don't know this error but you should consider that microsoft will switch off SMTP soon…
May you want to configur OAUT2 connection instead?

regards,