multiple duplicate emails sent or no email sent

we have two websites with multistore setup. Multiple duplicate emails are sent to customer randomly and in message queue I can see the emails are created only once. System admin are saying there might be some with application. Could this issue might be with multistore setup?

kindly help
thanks

I see your post is from 5 years ago but i have a similar issue using 4.50.1 insofar as I have 7 stores and get 5 duplicate emails every time, but cannot see a reason why. In the message queue I will see 5 ID's each with the same subject with identical to and from email addresses.
I'm guessing this is a multistore setting issue but cannot see what that is nor can I see anything significantly different across the 7 stores that might account for 5 behiving differently from the other 2.

Check if your application pool is using multiple worker processes - if it is, that's your issue, and revert to a single.

Thanks for the suggestion but they are all on the 1 IIS site with 1 worker process and seperate bindings for each domain.

[email protected] wrote:
Are these, as per the original post, "emails are sent to customer", or are they "Contact Us" emails?

All emails were affected be it a sale confirmation or a message via a contact form; however, I think it may be resolved. It was suggested privately that I check the message templates for duplicates. I found there were 5 of each. 4 of each have now been disabled and I hope that has resolved the issue.