Have not rebooted yet, so no blocking attempts, it has been running for hours with at least one reboot since the upgrade. I had assumed that is was vital as it is called Emergency but googling cleared that up, not much the wiser as to why it is needed though.

My other xp box wants to upgrade to same version now too. Will let that update tomorrow and see if it behaves the same way.

Overlpped post: Will try Johnny advice