What did I do wrong this time?

[vorpalbunny]

You're right, I was trying to access the FTP program through my browser, and I don't have one installed yet.

With the "There is a problem with this website's security certificate" warning page, I was trying to get in through here: https://glowhost.com/login/cpanel.php, the GlowHost SSL Secured cPanel Login, by filling in my domain name, username, and password. I've gotten into my control panel that way before, so I'm not sure why it's giving me such a dire warning now. Here's the address of the warning: https://glowhost.com/login/docpanellogin.php

Thanks so much to both of you for your help!