Hotmail has a new user interface
BUT it doesn’t work well in my browser. I couldn’t reply, I couldn’t get back to the inbox once I click on a message. The whole thing is just a disaster for me and I don’t know how to change it back. Seems like Microsoft is pushing this update batch by batch to their users.
Here’s a screenshot of the new interface:

(Microsoft Windows Live Hotmail does not play well with Firefox.)
Of course, it worked for Internet Explorer but…
Anyhow, I should note that I do like the cleaner design. The new calendar is better too. And the contacts. Everything’s better… if and only if it works.
[By the way, there is still a huge wide advertisement slapped above the mail interface. I just crop it away because it is an advertisement.]
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