The emails this fellow had sent us were answered. I'm not sure why he didn't receive a reply. I'll have our admin examine our email server. I know that we've been blocked in the past because of the odd complaint caused by people spoofing email from us and other such email mayhem.
My email is via Google Mail. Nothing showed up in the Spam folder. I don't know what sort of RBL/other spam filtering GMail performs.
P.S. This fellow's issue has been resolved by PM.
Yes, the issue has been resolved. Thanks!