Outlook and its mysterious ways

Is it possible to connect with Outlook Anywhere (RPC over HTTPS) via a proxy with authentication?

A: Sometimes.

Try this:

Setup the web proxy in IE

Create a folder in the mailbox, in its properties go to Home page, check Show home page by default for this folder, add some vaild URL in Address

Go to that folder, logon to the proxy when asked, and check remember user and password.

Close Outlook and open it.

Go to the same folder, verify that the page opens without asking user and password, and wait.

Tested with:

Outlook 2010

Windows 7 not joined to the same domain as ISA server.

Exhange 2003

ISA Server with NTLM Auth