I am using outlook for Mac 2011 version 14.1.0

Suddenly I am no longer able to retrieve new mails, my last mail to my inbox was 24.5.2016.  When I click the Send/Receive icon, I get the following error code 

The server for account "Hotmail" returned the error "Authentication failure: unknown user name or bad password. [Error="ProxyNotAuthenticated" AuthResult=0 Proxy=HE1PR0101MB2042.eurprd01.prod.exchangelabs.com:1995:SSL]." Your username/password or security settings may be incorrect. Would you like to try re-entering your password?

I have re-entered my password many times and deleted and re-instated my account but nothing is working.  I have had no problems in the past and have made no changes to my laptop that could cause this problem in the last 7 days.  I can send emails and can access my folders, contacts etc.

Has anyone got any ideas of how I can get my emails?