Dovecot- 2.3.11.3 with mdbox.

I have a situation where I can access (view) the e-mails when I use a web-based IMAP client, but NOT M$ Outlook (configured for IMAP).

Is there an easy way to solve this?

When I send an e-mail to the mailbox address, I can see it on the webmail, but not on Outlook.

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