Have a customers Machine with a puzzel of a problem

the problem:

While the Browser (IE) will load the Hotmail Logon page, entry of the username and password returns, after a reasonable wait, to the same logon page.
Entry of an invalid Password, will bring you back to the page with the Password error message
useing a different account on the PC returns the same issue
useing the users account on another PC no problems
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Cleared Cache, disabled Firewall, and anti virus, run spybot s&d, adaware, emptied TEMP/Windows Temp/user-Temp, recycle bin. Updated MS patches, re set security settings, cleared ssl state, checked the time and date, re registered the cryptographic dll files. Ran SFC, no result.
did a Autopatch update just to be extra funny..

so here I am stuck Google is not my friend with clues on this so i am hopeing that some here may have a hint for me on this one.. (please)

Ciao