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hoyty76's avatar
hoyty76
Iron Contributor
Apr 30, 2019
Solved

Conditional Access for external SMTP authentication

We only have one use for external services sending via Office 365 in an authenticated method. I was hoping to use conditional access to restrict only one account to be able to authenticate into SMTP. I want to block all other users from being allowed to authenticate into SMTP. Is this possible?

Conditional Access
  • Sauky's avatar
    Sauky
    Apr 12, 2022
    You can disable SMTP AUTH globally for your organization by using Exchange Online PowerShell. And then enable it per mailbox in the Microsoft 365 admin center or using Exchange Online PowerShell.
    https://docs.microsoft.com/en-us/exchange/clients-and-mobile-in-exchange-online/authenticated-client-smtp-submission

1 Reply

  • Sauky's avatar
    Sauky
    Copper Contributor
    Apr 12, 2022
    You can disable SMTP AUTH globally for your organization by using Exchange Online PowerShell. And then enable it per mailbox in the Microsoft 365 admin center or using Exchange Online PowerShell.
    https://docs.microsoft.com/en-us/exchange/clients-and-mobile-in-exchange-online/authenticated-client-smtp-submission

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