taking a look at their website for details on how to set up your email
Did you take a look here:
http://www.one.com/en/support/guide/mail/setting-up-mail-os-x
Seems to all the necessary steps to configure Mail.
Delete all those accounts that you created, the ones that don't work, and start again with the instructions
P
Hi. I'm a new Mac User and just added my one.com e-Mail accounts on my new MacBook Air.
Now I'm getting the error message "Client tried to access nonexistent namespace. (Mailbox name should probably be prefixed with: INBOX.)"
I tried to change the name and added INBOX. But that didn't help.
Can anyone help me with this issue?
Thanks in advance.
Matthias

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