Random

The message you are seeing at the bottom of the email (PLEASE NOTE: The member responding to your post has chosen not to reveal his or her email address. Therefore, you cannot reply to this message via email) only means that you are not able to respond by clicking reply within your email account. However, there is a way to send them a response ... go to their 'My Page' and respond to them from there. Neither of you has to unblock your email address.

You do not have to respond via email. If they are set up to be able to receive email, you can respond to them from their My Page the same way they emailed you.

Finding a member 'My Page' ... http://members.gardenweb.com/members/search.cgi
I believe it IS upper or lower case sensitive

GETTING EMAILS SENT TO YOU ... 3 Step process
1. Be sure you have a valid/current email address in your profile
2. In your profile, be sure you have the "Allow other users to send you email via forms at our site." box checked (at the bottom of the profile page)
3. When posting to a thread, be sure to check the box labeled "Check here if you would like copies of follow-ups to your message emailed to you" when you submit your post. (Below the "Message" box)
CLICK "save your member profile" button

You also have the choice to have your email address revealed or not revealed in your settings.

I noticed something that made me change my settings ... When you email someone, if they have their email revealed, GW will automatically show you the person's email address. Just in case any spammers ever come trying to harvest email addresses, I thought it would be a good idea to change my settings. Because I use my real, work email address in GW, not a fake throwaway address. Click the first link below and you will see an example of how you can see that person's email address. Typically, when I send a private message to someone using GW, I include my email address in the body of the message, so they can respond without having to search me out using My Page. But I can still keep my email address private within my settings.

I have sent a suggestion asking GW to make this message that appears at the bottom of the email more clear, because it is very confusing how they have it worded. You can send a suggestion too ...
Here ... http://www.gardenweb.com/auth/nph-logincheck.cgi?action=public_profile&user=/gwtamara
or here ... http://letters.gardenweb.com/letters/nph-ind.cgi