i'll try and see what i can find out... (i didn't know CS5 would even run on Win8.1 ! !)

There might have been a problem with the serial not being deacitivate before installing on the new compurter.

 

Also i'm not sure what update you are looking for? 

The message on the page (that you linked to) is the standard message you get whae you try to update beyond the last 2 versions (so going fron CS5 to CC 2014 won't happen).

are you just looking for the increamental updadte to CS5?

 

scott