Hi all we are a large software development house with hundreds of Virtaul environments we recently migrated our exchange environments from internal to 365.

we use an internal Linux SMTP server running Postfix to control the mail send from these environments. 

We have been testing this pointing the postfix to 

smtp.office365.com on Port 587, what we have discovered is that unless the send address need to have mailbox (can be shared) and the sending server address needs send as permission to that mailbox. so 

sending a test mail from server 1 via SMTP server called email address removed for privacy reasons

email address removed for privacy reasons  needs a mailbox with email address removed for privacy reasons having send as permissions

this seems a bit crazy as we could end up with hundreds of mail boxes

Can anyone help with better options

​Hi all we are a large software development house with hundreds of Virtaul environments we recently migrated our exchange environments from internal to 365. we use an internal Linux SMTP server running Postfix to control the mail send from these environments. We have been testing this pointing the postfix to smtp.office365.com on Port 587, what we have discovered is that unless the send address need to have mailbox (can be shared) and the sending server address needs send as permission to that mailbox. so  sending a test mail from server 1 via SMTP server called email address removed for privacy reasonsemail address removed for privacy reasons  needs a mailbox with email address removed for privacy reasons having send as permissions this seems a bit crazy as we could end up with hundreds of mail boxes Can anyone help with better options       Read More

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