To prevent Office365's spam filter from blocking incoming messages coming from our servers, you should whitelist the IPs we use to deliver messages to your mail server. To do this, please proceed as follows:
- Log in to the Exchange Admin Center.
- Click on Mailflow and then on Connectors.
- Click the plus sign.
- Select "Partner organization" for "From" and "Office365" for "To".
- Select "Use the sender's IP adress" and click "Next".
- Add the IP addresses from our website https://europeanmx.eu/de/mxstatus . Since the IP addresses can change, I recommend that you subscribe to the newsletter. You will then automatically be informed by e-mail about changes to the pool.
- Make sure in the following window that the option "Reject email messages if they aren't over sent over TLS" is selected and click on "Next".
- Check the settings and click "Save".
- Go to Mail flow> Rules.
- In the "Rules" tab, click on the plus sign and select "Bypass spam filtering".
- Enter a name for the rule.
- Select "Apply this rule if..." and then "Senders IP Address is in any of these ranges or exactly matches".
- Add the IP addresses from our website https://europeanmx.eu/de/mxstatus .
- Make sure that the setting "Do the following..." is set to "Modify the message properties > Set the spam confidence level (SCL) > Bypass spam filtering".
- Click on "Ok" and then on "Save".
The spam filter will no longer check messages from our filter servers and Office365 will no longer reject messages due to SPF.