Some BlackBerry PlayBook tablets that Research in Motion released last Tuesday are suddenly failing to restart. Some even simply stop working while in use and do not restart. InfoWorld.com experienced this issue with its own review unit after three days of use, and about a dozen users have reported the identical problem on RIM's BlackBerry.com support site.

The initial reports began on the evening of 20 April, one day after the PlayBook was released, though most users reported the problem after a few days of use. For units experiencing this "sudden death syndrome", the PlayBook's indicator light double-blinks when turned on but the screen remains black.

Some users have been able to reinstall the PlayBook OS from the BlackBerry Desktop Manager software, but InfoWorld has not: The PlayBook is detected by the manager software but is unable to communicate with it or reinstall the OS. Most users who've described the problem at the BlackBerry support site report they have also been unable to reinstall the OS.

RIM's support staff has not yet responded to the users on the support forum, and several users who called RIM said the support staff had no solution. RIM also did not respond to InfoWorld's inquiry.

It's unclear how many units are affected by the sudden death syndrome, though most reviews of the PlayBook have criticised its incompleteness.