Wrong Officer email message

I have an officer who says that my emails to the officer list always give him a strange message that he is not allowed to reply to it. I checked and I have the right email for him.

You haven't given us much to work with.  We always need your club number.  For email issues we also need at least a first name or last name of the person having problems, or in this case their officer role.  The 'strange' message they're getting would also be helpful.

As a wild guess I'd first look at what email address they are using when replying to your email - it must be either the primary or secondary email address they have registered on your website.