Dammit. Adobe sucks - how can they write software that, either when it creates the keys or modifies keys, limits the permissions to Read only for everyone? What's wrong with doing what's done on the other keys and make it inherit it's permissions from above?!
Anyway, rant over.
I've been asked to look into why someone keeps on getting the 1406 error when installing:
I've done the done thing and Google'd it and came across a few link including this one: http://www.riggsca.com/error_1406.htm but it just didn't work for me. I couldn't reset the permissions in any way even though my login was part of the administrators local group.
I had to reactivate my administrator account (I assume that creating another admin account would also do) and log in as that user before trying to install the software again.
Every time the install error would pop up I would browse in the registry to the key in question and reset the permissions by clicking on advanced and ticking the "Inherit.." and "Replace.." check boxes, applying it and removing the Everyone Read-only from the list and applying it again.
Go back to the installer and click "Retry" and do this again and again until all the permissions are reset.
Now it works.
One thing that may just be coincidence, but coincidence is something I'm fairly wary about, is that the HP 3300 wireless printer stopped working at the same time as this error started appearing. Strange but true...