Outlook Error Message

Question

People keep receiving this message when they sent something to my hotmail address.:

Delivery has failed to these recipients or groups: @hotmail.com ( @hotmail.com)

The recipient's email system isn't accepting messages now. please try resending your message later or contact the recipient directly.

However I get all of the emails. So why do people keep getting this message? It just started on Friday.

Thanks, Steve Allread