If you are using a hotmail or other Microsoft domain email service that will be the issue, MS likes to automatically block emails from ASC probably due to the high amount of users we have that get notifications thinking its a spambot......
Try switching to a non MS email provider, this should fix 99% of your issues.
Saskatchewan Age Verifier! Contact for more Info.
http://airsoftcanada.com/showthread.php?t=174161 - Honour & Respect your fellow players! #Airsofthonourandrespect