See the question and my original answer on StackOverflow

There is no official way to read Hotmail using HTTP(S). There used to be DAV but this has been phased out, here is the official statement:

Continuing DAV protocol retirement

Windows Mail & Outlook Connector both use a protocol named DeltaSync that is not documented.

Some people are trying to reverse engineer it like this guy: DeltaSync HU01 decompression code released, but there is asolutely no guarantee this will not evolve - in fact, you can be sure this will evolve :-)

So, you're better off with POP3: Hotmail and MSN Accounts POP3/SMTP Access