BlackBerry 7290 will not syncronize. Stuck on encryption udpate.

Occasionally when you plug a BlackBerry (specifically BlackBerry 7290) into your computer for syncronization with the Desktop Manager software it will not successfully syncronize or it will become stuck at the syncronization screen forever.
In addition, you may be asked to generate a new encryption code by moving your mouse around the screen for a while.The [...]