Microsoft is moving forward with their goal of completely getting rid of Basic Authentication. But there are always situations in which we cannot avoid it, for example with printers (Scan2Mail) or websites. These usually send the mail via SMTP, which Exchange Online also supports in principle.

Luckily, Microsoft has announced that Basic Authentication for SMTP will continue to work. With newer Microsoft 365 tenants, however, SMTP authentication is deactivated by default.

Enable SMTP - Exchange Online PowerShell

The following command can be used to activate basic authentication via SMTP for the tenant and one (or more) specific users.


$user = Read-Host "SMTP User/E-Mail"
Set-TransportConfig -AllowLegacyTLSClients $True
Set-TransportConfig -SmtpClientAuthenticationDisabled $false 
Set-CASMailbox -Identity $user -SmtpClientAuthenticationDisabled $false Code language: PowerShell (powershell)

ℹ️ The Exchange Online PowerShell module is required:

SMTP Exchange Online

SMTP configuration on the end device

With the following settings, e-mails can, for example, be sent from a printer or a homepage via SMTP.

EncryptionSTARTTLS (important)
Log inUsername of the sender
PasswordSet password

It is important that the user does not receive an MFA request from the sending device and that no password changes are pending.

You can find more Exchange Online topics here: Exchange Online | scloud