Ludek, I believe I have a positive resolution to this issue. On the troublesome computer I upgraded Adobe Reader X to XI. This instantly solved the problem!
In point of fact, I bet that there's nothing wrong with Adobe Reader X per say but perhaps with that particular installation. Installing a new version seems to have done the trick.
Thank you again for your assistance,
Robert
P.S. I do have another issue but will initiate it in another thread.