you need to hit the the spam inbox (if you have one) half the time the messages get sent there if you use gmail, so chances are other online and maybe some virus scanners may block mail from this address?... some get through some don't, probably due to the large userbase this site has and the people using it falsely getting flagged as spam...
write a little Arduino server to show a Postbox light up when you get mail, might be easier to get mobile phone to relay that info via bluetooth to cut costs....