my kinesis ergo keyboard would stop working with windows update pushed on us with some new power saver green updates.

the fix was to disable the "go to sleep mode".

posting this just in case someone else has the problem. this happens with other keyboards too, not just kinesis.

[2. Advantage keyboard not working after Windows computer goes to sleep mode

We have learned of a widely reported problem with Windows operating systems (XP & Vista) using third party keyboards (even though the problem has been reported with the Microsoft Natural keyboard as well) where the keyboard does not function after the computer enters sleep or hibernation mode. Fortunately there is a easy solution:

Go to Start-Settings-Control Panel, double click Keyboard. Click the Hardware Tab, highlight the "HID Keyboard device" and select Properties. Click Power Management. UNCHECK the box that says "Allow this device to bring the computer out of standby." Click OK. Now when your computer goes to standby or sleep mode, you will simply need to wake the computer by moving your pointing device. Your keyboard should now work perfectly fine.

For Vista users, go to Control Panel, Power Options, click "change plan settings" then "change advanced power settings" then go to "USB settings" and select "disabled."]

link to more-
http://www.kinesis-ergo.com/tech_support/trouble.htm