Duplicates can be caused by

     1) file access errors.

     2) duplicate incoming messages - sometimes caused by outlook 
combined with a virus scanner issue.


So check if msg*.rec shows the duplicates as 'arriving' more than once.  
And check if there is some problem deleting messages from your inbox.

empty your inbox, then examine the file system to see if it's empty

     tellmail path user@xya.com

     cd (path)/mdir/new

     ls -al

ChrisP.


On 16/01/2020 5:35 AM, John Wilkes wrote:
> I've been getting duplicate messages since a recent power failure.  Thanks to a UPS, I shut down the mail server and mirror cleanly, so no crash.  It's only certain senders that seem to generate duplicates.  I've received five copies of some messages.
>
> Any ideas what could be causing this?
>
> Currently running version 7.3o4-4 on a Centos system.
>
-- 
p.s. We'd love a link from your website to our new domain: https://surgemail.com if/when u have time.