Outlook for Mac error messages

I have just added 2 new imap email boxes to my outlook. I have them running on ipad and iphone with no issues but the laptop keeps popping up with an error message.

I keep getting the following:

"The server for account "Geffen Mike" returned the error "maximum number of connections from user +IP exceeded (mail_max_userip_connections). Your username/password or security settings may be incorrect. Would you like to try re-entering your password?"

I know the username/password for the emails are correct as i'am still able to send and receive.

Anyone got any clues as to how I can fix?

Thanks

Mark