Please check to see if you have gone over the disk space quota on this mailbox.
1. Login to cPanel
2. Click on 'Mail'
3. Click on 'Manage/Add/Remove Accounts'
4. Click on 'Show Disk Space Used' (right under account list)
5. Look at the disk space used vs. the disk space quota. i.e.
Notice that 'john@mysite.com' has used more disk space then disk quota
setup for this account. This will cause emails to be rejected with an
error of 'Mailbox is full'
This is normally caused by people using webmail, instead of an email
client. If you use webmail, you must clean out your sent mailbox,
depending on which one of the webmail clients you are using, you must
empty the deleted folder as well.
If you are not using webmail, then this because your email client is not
setup to remove the messages from the server upon download.
You may also increase you quota on the mailbox in question, but please
note that these quotas subtract from your total disk space of your plan.
i.e. If you are on our Plan-200 with 200 Megs of diskspace, and you set
the quota to 30 Megs, you now have 170 Megs for webpages and mysql
storage.
If this did not resolve your problem, please open a support ticket.
