If you cannot view the preview window in webmail, you will need to temporarily disable your firewall in order for it to show up. For information on how to do this, please follow the instructions below.
Disabling your firewall
If you have a firewall installed, it may prevent the preview window in webmail from showing up. You will need to either make an exception for port 8080 or 9999 TCP, or temporarily disable it before you check your webmail. For information on how to do this, please visit the following link:
How to disable your firewall