Email Setting - need help with outgoing emails

I’m having an issue with my outgoing email being marked as spam by outlook (office 365) and Gmail not being able to verify the sender, marking the email with a huge question mark.

Hoping someone can help please.

The set up is as follows

Domain is hosted with Ionos (formerly 1and1)
We subscribe to Office 365 with the relevant DNS records MX, TXT, CNAME etc

I have added the SMTP settings provided by Ionos in to the email settings page of TB. The email is sent but marked as above. Also, the message was received in Outlook but does not show in the sent box in Outlook which i would have expected.

I guess, i should not enter email settings for Ionos and somehow need to connect to office 365.

Anyone with experience who can help?


There’s a lot to unpack here. Emails are complex and Gmail has very good methods of checking if an email is safe or not. From Tadabase’s perspective we have very little we can do since all emails are proxied through whatever SMTP settings you’re using.

Here’s some recommendadtions I have:

  1. Add SPF records to your DNS
  2. Add DMARC records to your DNS.

I was able to verify that both of these are not present in your domain. You can test that here:

Learn more about DMARC here:

When you add these DNS records you’re essentially giving Gmail more info so they can verify that the emails came from who it says it came from.

This is beyond the scope of Tadabase support, but I’d be happy to help here however I can.

We’ve had really good success using SendGrid for outgoing emails. Sendgrid makes email domain verification easy and their deliverability is pretty reliable.

You can see a screenshot from my Sendgrid account:

1 Like

Hope this helps others.

It seems the issue arises from accidentally having 2 mailboxes for the same email address. Initially we used Ionos to manage our mailboxes using SMTP to sync accross devices. We switched to Office 365 2 years ago but thought the mailboxes would sync. At the time, we did not know they were 2 seperate email boxes.

When we set up SMTP in Tadabase it was sending emails from the old Ionos mailbox and not the Office 365 mail box. The solution so far is to add the records as Moe suggested, delete the Ionos mailbox and maybe use the outlook Pipe. :grimacing:

I have now been able to get emails sent via the app to be sent using SMTP with our office 365 account. Happy to be corrected if i have anything not quite right.

First, i ensured that i had SPF, dmarc and DKIM DNS records against the domain name. Microsoft had added these records but against an alias of

Office 365

  • Logged in to the firms office 365 admin account with admin permissions
  • Edit a user
  • select the ‘Mail’ tab
  • Click ‘email apps’
  • Check Authenticated SMTP’ mine was unchecked by default.

O365 check smtp option


  • settings
  • email settings
  • SMTP
  • enter SMTP send -
  • Port 587
  • your email address
  • your O365 password
  • Encryption ‘TLS’

My emails are now sending via our own domain without being marked as spam or other warnings. However, I believe i need to send all emails from the email account added to the email setting section whereas we would want emails to be sent from the users own email address. Haven’t tested how this works yet.