Outlook 2016 outbox stuck - Microsoft Community

i running outlook 2016 , when sending emails stuck in outbox.  when close outlook, warns me emails still in outbox , asks if want close it...and indicates send when restart outlook , indeed, when message sent. however, before sending want send, says sending 3 of 3 email messages, sends 1 in outbox put in there. 

to best of knowledge, cannot find these mysterious 3 of 3 messages, leading me think not showing somehow clogging outbox. have 'repaired' office using both offline , online versions, did complete removal of office using tool microsoft, reinstalled office, , still see same thing. online tech suggested try make new profile, did. worked first 2 or 3 messages , had same issue.

the challenge sent email gets stuck 90% of time, not always. , restarting outlook when outbox stuck succeeds in sending email.  have disabled add ins , still happens. , fact there 3 of 3 'phantom emails' sent before stuck email gets sent (on outlook restart) adding confusion.

now me workaround re-start outlook when want send message, far optimal.

any thoughts more welcome.

thank you!

possibly read receipts, not visible in outbox.

if stuck mail, sent when re-start outlook, caused integrated add-in

you need state add-ins shown, whether activated or not

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