All emails get forwarded to the postmaster because they "do not have local recipients"

This means POPcon does not recognise your domain as a local domain and cannot match recipients to Exchange users.

Solution

In POPcon's POP3/IMAP configuration, find the "Accepted Recipient Domains" field and add your domain name — without the "@" symbol. For example, enter yourcompany.com, not @yourcompany.com.

POPcon uses this list to filter and route recipients correctly to Exchange.

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