how to stop duplicate emails when transferring to new server

[asmithjr]

I was wondering how to stop duplicate emails when transferring to a new server.

I used the Transfer tool in WHM to transfer my first group of accounts to a new server. This morning I was notified from users that they had hundreds of emails. Upon researching we found that they were emails they had already read.
I did ask a couple and they said they were using IMAP.

My questions are:
Have others experienced this issue?
How do you keep this from happening?
What other steps did I miss in transferring the accounts other than just using the Transfer Tool in WHM?

 

[cPanelMichael]

Hello

Did you update the name servers for the domain names, or did the IP addresses remain the same? It's possible the email data was copied over, but the domain name did not propagate until later, at which time all of that email data was downloaded again.

Thank you.