In Pictures: Microsoft's 13 biggest wins and fails of 2012

Fail: No Windows Phone 7.8 for you!

Many Nokia 900 users were infuriated to learn that their new, state-of-the-art Windows Phone 7 devices would be rendered obsolete less than a year after the operating system's launch. Microsoft tried to make amends for the fact that WP7 owners couldn't upgrade their devices to Windows Phone 8 by promising an interface overhaul called Windows Phone 7.8. The new upgrade would at least make Windows Phone 7 handsets look as though they had the new operating system.

But after saying that WP7.8 would arrive in the fall, Microsoft in November pushed the cosmetic update back to 2013, disappointing their unhappy WP7 customers once again.