Now this is interesting. I made no changes as I was finished for day when I got your reply above.The following strange behaviors occur:
1> I checked the site 1st thing and http://outofchaos.net/gsc/www/products_results.php?Category_ID=6 came up fine on both testing and remote servers.
2> However, when I did a Search using products_search.php, I got 'No Results.'
3> Then when I went back and tried http://outofchaos.net/gsc/www/products_results.php?Category_ID=6 again, I get 'No Results'
4> I Go back to Search and enter Category - 'Boulders' - still get 'No Results' but now http://outofchaos.net/gsc/www/products_results.php?Category_ID=6 which is 'Boulders' works again but 'Gardenrock bags' which is http://outofchaos.net/gsc/www/products_results.php?Category_ID=32 does not - gives me 'No Results'
5> I go back to Search and enter Category - 'Gardenrock Bags' - - still get 'No Results' but now http://outofchaos.net/gsc/www/products_results.php?Category_ID=32 which is 'Gardenrock Bags'' works again but 'Boulders which is http://outofchaos.net/gsc/www/products_results.php?Category_ID=6 does not now - gives me 'No Results'
6> I made the Code change you suggested and still get same results above.
7> I removed 'Category' from the Products table and it totally broke the pages so I put it back
Looks like the act of using products_search is caching something that negatively affects using the Products dropdown to select Categories via products_results.php
Any clues here that might suggest a solution to you?
FYI - I removed products_results.php from my live server as I have an interested party reviewing the Product pages and I can't afford to have it behaving irratically. But I attach the latest products_search.php here if it helps.