Have clients using EWS on Mac Mail app (exchange type account) . Recently they have been getting duplicate sent items . So each email sent appears twice in sent items.

This never used to happen, anyone else see this behaviour?

 

I see plenty comments about this being an issue with IMAP (on apple forums) , with people passing blame between Apple and Microsoft. Any one got any experience on this ? as I said this behaviour is relatively new about the last month or so ? 

 

Be curious to hear if anything to do with SM as my gut feel is this is since upgrade to SM 14.3

 

Does 14.4.xx  resolve this