That request didn't take long. Thank you houzz! Copying the info below from member phyllis's post at The Seed Exchange. Go to https://www.houzz.com/editProfile Edit Profile -> Advanced Settings -> Privacy Settings -> Who can message me -> select "Allow anyone to message me" (near bottom of page)

I think that "follow this thread" is now called bookmarks. There's a button called that underneath every post, but there's also one underneath the first post. Clicking the one underneath a comment bookmarks that specific comment and I've found it to be very helpful when you're following a long thread, because it basically marks your place in the thread so you don't have to scroll for ages. Clicking the one at the top just saves the thread itself.

Hi Georgect: If the person has allowed anyone to message them, by setting it up in their personal profile-advanced settings, then you can send them a message by clicking their name to go to their profile and then clicking the message link on the upper right hand corner. If there is no message link, then they have not chosen to receive messages. You can also send a message if that person is following you. You can try it by clicking my name, because I have elected to receive messages from anyone. You should see the message link when you go to my profile page.

Messaging in Houzz is quite restricted because the default setting is: "Allow users I follow to message me" (under Advanced Settings). So if you want to message someone and they have the default setting you will only be able to do it if they follow you. Right now it looks like everyone has default settings and hardly anyone is following anybody, so messaging is practically disabled. There are two ways to make it activated: increasing the following or changing the setting to "Allow anyone to message me". Ironically, this has to be done by the potential recipients, not the people who are eager to send a message. We have changed our setting, so that people can find out how messaging would work. Most likely there will be a link in our profile or when hovering over our username.