CF10 and Exchange 2010 - Can't Log In

[Tom Woo]

No matter what I try, I can't get this to work:

<cfexchangeconnection action="OPEN" connection="conn1" server="[server]" username="[domain]\[username]" mailboxname="[mailbox]" password="[password]" protocol="https" formbasedauthentication="True" formBasedAuthenticationURL="https://[server]/owa/auth/owaauth.dll" serverVersion="2010">

I've followed the instructions to the letter.  The Exchange server has HTTPS enabled.  It is running Exchange 2010.  I've installed the HTTPS certificate on my server.  Still, I get this:

Could not login to the Exchange server.

Verify the server name, username, and password. Ensure that proper client certificates are installed.

What the heck am I doing wrong?