I have upgraded my Acrobat to version 9.1.4 and now get the following error message when I try and open (as opposed to saving) a pdf file on line:

"Could not find Acrobat External Windows Handler"

Judging by the number of Google hits, this appears to be a common problem within Acrobat but no solution appears.

I've searched the Adobe site with no success.

Anyone got any ideas?