I switched my primary alias from a 'gmail.com' to a 'outlook.com'.

However, due to i am using the 'outlook.com' to log in windows now, i am unable to log into xbox apps and halo:spartan assault due to the fact that the xbox account of mine is still named after the 'gmail'.

I have reached microsoft support from the xbox guys before and they say they've nothing could help me.

Each time i clicked on the account settings on xbox.com  logged, it shows something like:
Oops... it should not be happening.
date:26/7/2013 2:34:44
code:B0FE51E9A404A3
s:3yG5Dj0XoroAhZLaW0Z5OQ==
id:a1f92d18-77e9-4a7a-b7cb-e657c0245d79
req:4143a59d-b388-44ac-b912-fd9e6b2677fe

I can still log into it inside desktop edition of my xbox for gta4 or wtsoever, but i can't do it on the metro apps which annoys me. I really want to play my Halo Spartan Assault.