How To: Set Up Forwarding Rules in Office365

A key part of setting up your own custom support emails with Desk365 is making sure you’ve set up the correct forwarding rules so that emails sent to your custom email are forwarded to Desk365. In this article we’ll go over how to do this in Office365.

The first step is to identify the Desk365 provided email address to which you’ll need to forward your emails. For example, in the setup shown in the image below, the custom support email is and the email to which you need to forward is:

how to set up custom support email address in Desk365

Set up Forwarding in the Microsoft365 Admin Center

The recommended way to set up forwarding is from the Microsoft365 Admin Center. These are the steps you need to take to set up forwarding on your Office 365 account:

1. Login to your Office 365 portal using your administrator account. From the menu on top, click Admin > Exchange to open Exchange Admin Center.

manage mailboxes in exchange admin center

2. From the menu on the left, click Mail Flow to create the forwarding rule.

3. In the Rules tab, click the ‘+’ (plus) button and select Create a new rule.

create a new rule in Office 365 exchange admin center

4. Enter a name for this rule. We’ve given Rule Name as ‘Desk365 forwarding rule’ for this example.

give rule name in exchange admin center

5. Under “Apply this rule if…” option,  choose: The recipient is.

6. From the next page, select your company’s support email address ( and click OK.

select your company’s support email address in the recipient is dialog box in exchange admin center

7. In “Do the following… option, choose ‘Redirect the message to’.

8. Paste the email address Desk365 provided ( and add it in the ‘Check names’ text box.

desk365 provided email address in the redirect the message tab

9. Now, click on the check names button after you enter the email address.

10. Click OK to leave this page and then click Save from the previous page.

new forwarding rule set up in exchange admin center

11. View and verify the configured Forwarding rule by sending an email to your custom support email address and check if a ticket is created in Desk365.

Set up Forwarding in Outlook

These are the steps you need to follow to set up the forwarding rules correctly in Outlook

1. Login to your Outlook account.

2. At the top of the menu, choose Settings -> View all Outlook Settings. A Setting dialog box appears on the screen.

3. Choose Settings > Mail and click on Forwarding option.

email forwarding settings in outlook

4. Choose the ‘Enable Forwarding’ checkbox and enter your support email address ( for activating email forwarding for your account.

setting up email forwarding rule in Office 365 email

5. Click Save.

Now that you’re done with forwarding, you can refer to our previous article in which we’ve explained the steps needed to configure your custom support email in Desk365.

Common Forwarding Errors to Look out for

1. Avoid setting up forwarding using the ”Rules” option under settings. This results in emails being forwarded with a “FW:” prefix and the Contact not getting set up properly within your helpdesk.

outlook rules

2. If you haven’t done already, we suggest enabling external email forwarding in Microsoft 365.

If a user has set up an automatic forwarding rule to an external address in their Microsoft 365 mailbox using Outlook, the message will not be forwarded when the rule is triggered. Instead, the user will receive a non-delivery report (NDR) indicating that the message was not delivered.

‘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)’.

Even though a user sets up forwarding, a Global Admin has to first enable external forwarding. The outbound spam protection settings and automatic external forwarding can be enabled for any mailboxes by a Microsoft 365 administrator.

Here are the steps to do:

(i) Log in to the Microsoft 365 Defender Portal as a global admin.

(ii) Navigate to Policies & rules -> Threat policies.

threat policies in Microsoft 365 defender

(iii) Choose ‘Anti-spam policies’ option here.

anti-spam policies in Microsoft 365 defender

(iv) Locate the ‘Anti-spam outbound policy’ in the list and select ‘Edit protection settings’.

select anti-spam outbound policies
anti-spam outbound policy edit protection settings

(v) Look for the ‘Forwarding rules’ section and select the ‘On-Forwarding is enabled’ option from the dropdown menu under Automatic forwarding rules to allow email forwarding.

on-forwarding is enabled option

(vi) Save your changes.

All your Microsoft 365 users can now configure automatic email forwarding to external mailboxes in Outlook.

3. We also recommend you to set up DKIM records for your domain.

This blog post explains in detail about the importance of setting up DKIM for your domain.

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