Zune 30GB players froze on 31 December 2008. The fix was to wait.

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New Year's Eve, 2008. Zune 30GB owners wake up. Their players are frozen. Microsoft's fix? Wait for tomorrow.

The Zune was Microsoft's music player. The 30GB was its 2006 model. Midnight Pacific, 31 December 2008. A new day starts. And the players lock up.

Here's the twist. 2008 was a leap year. 366 days. So 31 December was day 366. A day that comes once every four years.

The villain? A bug in the internal clock driver. In how the device handles a leap year. The last day broke it.

Not a software update. Microsoft posted instructions instead. Step one: let the battery die. Step two: wait until after noon GMT, 1 January 2009. Step three: charge it. It should start normally.

Player still working? Don't plug it into a computer before noon GMT. It'll freeze too. And opening it to pull the battery? A bad idea. Warranty void. Just wait.

Rare dates break code. Leap days. Day 366. Month ends. Set the clock forward and test them. Waiting four years isn't a test plan.

Full story in the article.