I have an article for you that will help you troubleshoot this issue with your email account:
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Thank you for your reply.
I followed the link and ran the troubleshooting guide.
All items mentioned are working ok (password, connection doctor, service provider etc.)
Eventually the last thing on the list is to "rebuild" the affected mailbox. Strangely when I choose the gmail inbox, the rebuild option is grayed out (non selectable..)
The other two mailboxes, iCloud and exchange, do have the option "rebuild" active.
I believe the issue is with this specific computer (Mac mini), as my Macbook Pro runs the mail program with all three acounts flawlessly.
Any other suggestions will be appreciated.
Eric thank you for your reply.
I must admit that I'm a bit reluctant to delete the account on the mini, as the pop up message says it will delete the account on the macbook as well..
Is there any way to have the account deleted only on the problematic computer?
I decided to go ahead, I deleted the account than added it again.
Unfortunately it didn't solve the issue, the gmail account is still not responding.
If there are any other thoughts, please advise.