How to fix error: “a custom mail flow rule created by an admin has blocked your message”: Office 365

Mail flow rules (also known as transport rules) have actions that define what you wish to do to messages that satisfy the rule’s requirements. You may make a rule that sends messages from particular senders to a moderator or adds a disclaimer or customized signature to all outgoing messages, for example. Additional attributes are usually required for actions. When a rule redirects a message, for example, you must indicate where the message should be redirected. Multiple characteristics are accessible or necessary for some operations. For instance, transport tule created by an admin has created an error which states “a custom mail flow rule created by an admin has blocked your message”. So how do you fix the error: “a custom mail flow rule created by an admin has blocked your message, follow the steps below to see how.

Step by step process – How to fix error: “a custom mail flow rule created by an admin has blocked your message”: Office 365

  1. First, sign in to your Office 365 account.
  2. Use the app launcher and navigate to admin.
  3. In the admin dashboard, under “admin center”, click on “Exchange”(you may need to click “Show all” to access).
  4. In the Exchange dashboard, click on “Mail flow”.
  5. Then click on “rules”.
  6. Then click on “Mail”.
  7. Here select “Inbox and sweeping rule”.
  8. Here you can delete the rule, if not you can move to the next step.
  9. Under “Mail” >> “Accounts” click on “Forwarding”.
  10. Ensure “Start forwarding” is enabled.
  11. Enter your email address.
  12. Then click on “Save”.

This will then allow you to start receiving forwarded and sent emails from other mailboxes within the network. Starting a transport rule overrides the current restrictions posed by the administrator’s rule. The transport rule by the administrator is not implemented when forwarding emails using the forward option. 

Users only get the non-delivery report (or NDR) if the original sender (not the mailbox with the forward setup) is inside the organization when we create the Inbox and sweeping rule. If the sender is from outside the company, the message is banned without an NDR to the internal mailbox where the rule is set up.

After prefixing the email, it should be forwarded to an external inbox or email address, but it should still be kept in the application support mailbox for further Rules to be applied. This is something we used to do using the “Connected Account option,” which worked great.

However, the email is destroyed following a successful forward or redirect. Users are unable to locate the email in their sent, trash, or deleted folders. It’s just not in the inbox. The approach described above, on the other hand, correctly gets the email.

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Mail flow actions  – Exchange Office 365

The answer that appears in the “Do the following” area when you pick an action in the Exchange admin center (EAC) is frequently different from the click route you specified. Also, instead of following the entire click route when creating new rules, you may occasionally (depending on your settings) choose a short action name from a template (a filtered list of actions) instead. The EAC column in the table displays the short names as well as the complete click path values.

Although a limited subset of activities accessible on Mailbox servers are also available on Edge Transport servers, certain actions are exclusively available on Edge Transport servers. Because Edge Transport servers don’t have an EAC, you can only manage mail flow rules in the Exchange Management Shell on the local server.

Mail flow rules created and configured on Mailbox servers are saved in Active Directory, and the Transport service on all Mailbox servers reads and applies them. When you create, amend, or remove a mail flow rule, the change is replicated throughout your organization’s domain controllers. Exchange is able to provide a uniform set of mail flow rules across the organization as a result of this.

The local instance of AD LDS on the server stores the mail flow rules that you build and install on Edge Transport servers. On Edge Transport servers, there is no automatic replication of mail flow rules. Only communications that pass via the local server are subject to the rules on the Edge Transport server. You can clone the Edge Transport server configuration or export and import the mail flow rules if you need to apply the same set of mail flow rules to several Edge Transport servers.

In-depth step-by-step process – How to fix error: “a custom mail flow rule created by an admin has blocked your message”: Office 365

Step by step breakdown:

  • First sign in to your Office 365 account.

Use your account details or if you have a current Skype account with the Office account in question, you can use this.

  • Use the application launcher to navigate towards “Admin”.

The launcher is illustrated by nine dots in the right corner, click on it and find “Admin” as shown above.

  • In the admin dashboard, under “admin center”, click on “Exchange”(you may need to click “Show all” to access).

In this example “Exchange” was pinned to the menu bar, however, in your dashboard you may need to click on “show all” which will bring you to the Exchange panel.

  • In the Exchange dashboard, click on “Mail flow”.

Mail Flow is a drop-down option so it will expand the options it holds, it will not open a new window to display all the options it has present.

  • Then click on “rules”.

This is where you can create new rules relative to restricting users.

  • Then click on “Mail”.
  • Here select “Inbox and sweeping rule”.
  • Here you can delete the rule, if not you can move to the next step.
  • Under “Mail” >> “Accounts” click on “Forwarding”.
  • Ensure “Start forwarding” is enabled.
  • Enter your email address.
  • Then click on “Save”.

That’s it for this Blog thank you for taking time out to read our content, please feel free to email our team about how it went if you followed the steps or if you need more help with the questions we answered in this Blog.

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Saajid Gangat

Saajid Gangat has been a researcher and content writer at Business Tech Planet since 2021. Saajid is a tech-savvy writer with expertise in web and graphic design and has extensive knowledge of Microsoft 365, Adobe, Shopify, WordPress, Wix, Squarespace, and more! You can connect with Saajid on Linkedin.

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