I needed to change my old email that I'm using in hubspot over to my existing att.net account. I have gone into adding a new email address, I have put in my username, and correct password for att.net. I have put in the appropriate imap and smtp info, and it will neither allow me to update this account, or it says my credentials are invalid... I've been trying to work on this for over an hour... HELP!
Check whether your old email still working and sending and receiving emails. If it is then it should not give an email. Then use this article to change the email address: Change your HubSpot user's email address
Hope this helps!
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