Public bug reported: When a new mailman subscriber is created with the email of an already existing mailman subscriber or user a `409` code with a message `user already exists` is returned by the postorius but when the same email but now case sensitive is used a `500` code with message `server error code` is returned. The latter should also return a `409` instead of `500` as it is misleading. Although the mailman core is giving `AssertionError: User should have had linked address` in both the cases`. ** Affects: mailman Importance: Undecided Status: New ** Tags: mailman3 -- You received this bug notification because you are a member of Mailman Coders, which is subscribed to GNU Mailman. https://bugs.launchpad.net/bugs/1425359 Title: 500 error code shown by postorius instead of 409 error code To manage notifications about this bug go to: https://bugs.launchpad.net/mailman/+bug/1425359/+subscriptions