Book a demo
Is your documentation AI-agent ready? - Get your free Agent Score in 30 seconds!
Enable external forwarding in Microsoft365
SaaS

Enable External Forwarding in Microsoft 365

• Published: •

Updated on Aug 31, 2026

✨ Try Document360
View all

AI Summary

  • SaaS companies can make changes that affect business operations. The blog describes an incident involving Office365/Microsoft 365 email forwarding to Freshdesk.
  • Support addresses such as support@ and contact@ forwarded incoming messages to Freshdesk mailboxes, but no support tickets were raised for almost a week.
  • Emails failed with “550 5.7.520 Access denied” because the organization did not allow external forwarding, following a security change in Office365/Microsoft365.
  • The stated fix is to create an outbound policy in the Office 365 security and compliance portal, enable automatic forwarding, and apply it to selected support/contact senders.
  • The same issue may occur with external customer support products including ZenDesk, Intercom, Help Scout, JIRA Service Desk, and Hubspot.

AI-generated content. It may contain errors.

See Document360 in action

One of the disadvantages of running your business on SaaS-based products is you never know the changes the SaaS companies make and the impact on your business.

Recently we had such an incident, we use Office365 / Microsoft 365 as our email provider and Freshdesk as our customer support platform. All the customer support emails like support@, contact@, etc are all configured to forward incoming emails to the corresponding Freshdesk configured mailboxes.

We noticed there were no support tickets raised for almost a week. When we logged in directly to the support mailbox, we saw a bunch of emails all failed with the following message

Delivery has failed to these recipients or groups:
Your message wasn’t delivered because the recipient’s email provider rejected it.

The message also contained a bit more detailed description

Remote Server returned ‘550 5.7.520 Access denied, Your organization does not allow external forwarding. Please contact your administrator for further assistance. AS(7555)’

This is due to a recent security change in Office365/Microsoft365. It makes sense to control the outbound /external email as an administrator. Since it increases significant risk if someone can get access to an email address. 

How to fix this issue?

The fix is fairly straight forward.

  • Login to Office 365 security and compliance portal (https://protection.office.com/antispam)
  • Navigate to Threat Management > Policy (on the left-hand side)
  • Click the button “Create an Outbound policy”
  • Provide a friendly name (we called it “Freshdesk – allow forwarding policy”)
  • Open the “Automatic forwarding” section and set “Automatic forwarding enabled” to “On – Forwarding is enabled”
  • Open the “Applied to” section and click on “Add a condition”
  • Choose “Sender is” and on the RHS just select all the support/contact email addresses you wanted to forward. Our configuration looks like

office 365 anti-spam external email forwarding

We used Freshdesk, however, you’ll experience the same issue with any external customer support product like ZenDesk, Intercom, Help Scout, JIRA Service Desk, Hubspot etc

Centralize all your documentation and make it easily searchable for everyone.

cta

Saravana Kumar

Saravana Kumar is the founder and CEO of Kovai.co, the bootstrapped SaaS company behind Document360, Turbo360, and BizTalk360. He spent a decade in Microsoft integration consulting in London for firms including Accenture, Fidelity, and Microsoft, and has been a Microsoft BizTalk Server MVP since 2007. He launched BizTalk360 in 2011 and founded Document360 in London in December 2017, after a company-wide hackathon produced the first prototype. Kovai.co now employs roughly 300 people across London and Coimbatore, serves 2,500+ customers, and has publicly crossed 10 million dollars in ARR. He writes on bootstrapped SaaS growth and product strategy.

Read more
Request Documentation Preview