Split from this thread.

I have that problem too. I'm aware of a colleague trying to email me and the email bounces back their end. When I try to email them, it also does not send, and I get an error message (using Windows Live Mail 2011). It is frustrating as you do not know how many emails are not getting though to your inbox i.e. customers. I know of two email addresses that I cannot send to, so I have to send emails to them from my personal Hotmail account. I have checked related junkmail settings.