Dear Heather,
Your problem comes from the way the different operating systems of the servers you chose to host your sites work. Your question has nothing to do with our software. Per our support policy we can only provide support for our software products, not the server they are running in (which of course includes your server's operating system).
I understand your frustration with having to change the URLs to several products. However there is NOTHING you can do at the .htaccess level to avoid it. Quite simply, it boils down to how each operating system deals with filenames in the file system used by the server. On Windows the file names ABC.txt, Abc.txt, abc.txt and ABC.TXT refer to the same file because the NTFS and FAT/FAT32 filesystems are case-insensitive. On Linux servers the same file names refer to four different files because the underlying filesystem (usually: ext4) is case-sensitive.
Pro tip: This is the very reason everyone is using lowercase filenames on the web. They are guaranteed to always work, no matter the server technology. Referencing a file with a different cased filename than the one stored on disk is bound to land you in hot water, which is exactly what happened.
Again, please let me state in no uncertain terms that your problem has to do with the operating system, NOT .htaccess. What you are trying to do is impossible at the .htaccess level. Even if it was possible it would be a suicide as far as performance is concerned. The filename IMAGE.jpg consists of 8 characters which can be represented in either lower or uppercase. According to what you've learned in Statistics 101 this results in a number of possible permutations expressed by the quotient of factorials 8! / (6 - 2)! = 8! / 4! = 5 * 6 * 7 * 8 = 1680 permutations. For this simple image alone your server would have to test all 1680 permutations to find out the correct file name. This translates to a third of a second. If you have a longer filename like oriental-carpet-oc12345-closeup-small.jpg you are looking at millions upon millions of permutations. So even if what you wanted was possible with .htaccess rules (it's NOT) your site would be so dead slow that you'd be looking for a way to make it faster. And the only such way would be, you guessed it, editing all 700 products.
Also, FYI, the block of code you pasted is the code required by Joomla! to have SEF URLs. If you would remove it you would have no SEF URLs such as http://www.example.com/products/carpets.html. You would instead need to have ugly URLs such as http://www.example.com/index.php?option=com_eshop&view=categories&task=show&cat_id=1234&layout=carousel. So even if you do away with .htaccess Maker and use Joomla!'s own .htaccess file (renaming htaccess.txt to .htaccess) you're still going to have the same code. On top of that this block of code DOES NOT have anything to do with the file case for the simple reason that you are trying to access a lowercase named file (image.jpg) with an uppercase name (IMAGE.jpg). Since your new server has a case-sensitive filesystem on a case-sensitive operating system the file you are requesting DOES NOT exist. If you're wondering, this is why it's being picked up by the Joomla! SEF URL section of the .htaccess: it only handles requests to files and folders which physically do not exist on your server.
So, let's recap. Your problem is with your operating system and your unfortunate naming choice of files. We can't offer support for anything except our own software, per the support policy you agreed to, therefore we have to close your ticket.
Nicholas K. Dionysopoulos
Lead Developer and Director
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