E-mails sent from the Campaign Manager are not being received

There are several possibilities that would cause users or recipients to not receive e-mails from your campaign manager. This may in some cases also apply to test messages sent from the campaign manager.

The most common reason is the e-mail is being filtered or blocked as spam.

If you are using a Yahoo! or Gmail e-mail address, or others, as your "from" e-mail in the Campaign Manager, your e-mail will likely get blocked.

https://help.yahoo.com/kb/postmaster/yahoo-dmarc-policy-sln24050.html
https://support.google.com/a/answer/2466580?hl=en

It is recommended to use your e-mail address for your domain name to send e-mail from the campaign manager, such as info@yourdomain.com.

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