For a user to access the Server using HTTP, Allow access using HTTP protocol must be selected at the user or user setting level, in addition to being allowed on the Site, per the instructions below.
To enable HTTP transfers at the Site level
In the Administrator, connect to the server, then click the Server tab.
In the left pane, click the Site you want to configure.
In the right pane, click the Connection Options tab.
Select the Allow HTTP Transfers on Port check box, then provide the port number. The default port number is 80.
Click Apply.