I have an outlook 2010 client, connected to exchange 2010 server on SBS 2011
When I first set up the account I hadn't set the mailbox sizes, so when mail was imported it eventually gave a mailbox full error.
However, since then I have set the mailbox size for this user to unlimited and for the server to unlimited.
I am having no problem sending and receiving mail, however Outlook displays the red cross and "Mailbox Full Your mailbox is full, you may not be able to send or receive items" message at the top of outlook, and a similar message when I send mail.
If I connect from my laptop or with OWA there is no error, and like I say there is no actual problem besides the annoyance of the error message.
I don't want to create a new profile, even though I am confident this will fix it - there are too many things configured the way I like this