Cant log in to email (redirected to login page)

I cannot log in to email.
I point my browser to http://webmail.MyDomain.com
I enter my email address and password (yes, it's the correct password).
When I click "Login", nothing happens. The email address and password get blanked out and I am still on the login page.

This also happens if I point my browser to https://MyDomain.com:2096

Is there a known email outage on the East Coast (where my server is)? When will this be resolved?

Thanks.