Microsoft Updates yesterday - impact today

24 hours ago, 15 updates were downloaded onto my Win7 laptop and were installed successfully (I assume) at switch off, when the usual 'Installing Updates - Do Not Switch off Power" (or similar) warning appeared.

When I switched on just now there was a message "Applying Update operation nnnnn of 45,491". This was before the Compaq logo appeared and before Windows started.  The word "registry" appeared most of the time.

This was followed by Widows starting, then "Preparing to configure Windows updates".

It's the first time something like this has happened - has anyone any idea what happened and why, please?

 

I've since been told that it happened to a friend last night (GMT = 12 hours ago).