And it's driving me around the bend.
This has been happening since March for the desktop/web client and I've finally sat down to sort it out tonight and can't get it to work at all.
My phone receives the emails fine which is why I've managed to soldier on for so long but the web application just won't renew my inbox or let me successfully re-add the account for inbound/POP3 messages. Outbound messages - send as 'example@live.co.uk' - works fine.
I've even reset passwords to ensure that isn't the reason and it still bounced me an authentication error.
Any suggestions?