[Dovecot] dovecot: lda(root): Fatal: Invalid user settings. Refer to server log for more information.

[/dev/rob0]

On Fri, Nov 16, 2012 at 10:15:24PM +0000, Ben Morrow wrote:
> postfix's local(8) will not allow you to deliver mail as root.

Strictly speaking it will deliver to/as root, but not if invoking 
commands, which is what the OP was doing.
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