Messages getting marked as spam when you send from your own domain name using Gmail?

We recently heard from a couple of customers who set up Gmail to “Send mail as” a different email address at their custom domain name many years ago, and who are now having problems sending mail to people who use Outlook.com for their mail service (the messages were wrongly being flagged as spam at Outlook).

If this happens to you, it’s because the way Gmail used to set this up doesn’t interact well with modern email providers. The way they send these messages makes it look like a “spam forgery” to providers like Outlook.com that check for DKIM and SPF.

You can easily solve this by deleting the address in Gmail, then re-adding it. (If you’re one of our customers, the “Using Gmail to send messages” section of this page on our website shows the settings to use at Gmail.) Google will then set it up in a better way that works with modern email providers.