Thanks, Andre, for the suggestion! I added the .htaccess file as recommended in the article which was linked from your response -- since my website is hosted on a remote commercial server I am unable to change the overall PHP memory limit on the server itself. However, I am still getting the same "resource module needs upgrading" error statement. Because of the context (or lack of context) when I see this error, I am not really able to discern which module(s) is causing the problem. If it was a module that I don't plan to use, then of course I would attempt to delete it altogether. Unfortunately, I can not tell which module is causing the problem.
Any other suggestions? Thanks again.