Client tried to access nonexistent namespace. (Mailbox name should probably be prefixed with: INBOX)

[Israel_Paya]

A customer of ours, who uses Mail from Mac, after last cPanel/WHM upgrade cannot send messages or even delete the message. How can I solve, please?
The error says ...
Client tried to access nonexistent namespace. (Mailbox name should probably be prefixed with: INBOX)

 

[kdean]

In Mail's Preferences, go to Accounts, select the email account, switch to the Server Settings tab and click the Advanced IMAP Settings button. There the IMAP Path Prefix can be set to INBOX.

 

[Israel_Paya]

Thank you so much for your reply. Mail's Preferences ... where? I cannot find how to access Mail's Preferences. Thank you.

 

[kdean]

In your client's Mail app on their Mac.

 

[Israel_Paya]

Thank you so much indeed. I am going to try. Best regards.

 

[cPanelLauren]

Let us now if that resolves the issue, @kdean thanks for the insight!

 

[Israel_Paya]

It seems it is working now. Thank you so much indeed! Best regards,