I find it strange that Java 6 Update 25 won't work with your machine.. Both Update 7 and Update 25 are basically the same except that Update 25 includes some security updates that are vital to your computer security when surfing the internet.. Going back to Update 7 could cause your computer to become infected should you surf the internet at the wrong sites.
So... first we need to know the operating system you're using, including which service pack it has installed.. For example: Are you using Windows XP SP3? Something else.
What type of credit card "machine" are you using? It must be connecting to the internet but why does it need Java? Have you tried checking the machine manufacturer's website to see if there are any firmware/software updates for the credit card machine? It might be the ideal solution so you can keep Update 25.
Next, what have you tried in order to remove Java 6 Update 25? Normally, it should be easily removable using the Control Panel/Add-Remove Programs section.. If it's not uninstalling correctly, what type of errors are you seeing? We need the EXACT error message please.
There is a Java removal tool (JavaRa) at the link below which might help. Download the .zip file to the computer, unzip it to a folder of choice, then run the Javara.exe.
http://raproducts.org/wordpress/software
Next, in order to reinstall Java 6 Update 7, you'll need to have an installer to do so.. You should be able to retrieve an older version of full offline Java installer by finding it at the site below:
http://www.oldapps.com/java.php
Hope this helps and let us know more.
Grif
For my business I need to have Java 6U7 in order for my credit card machine to work. It worked great....until I allowed an update 6U25. Now it will not work! I have tried to remove the 6U25...it will not let me. I have removed the 6U7 and then tried to remove the 6U25...it still would not let me. I have tried A LOT of different things! I need some help. (Yes, I did try the 'experts' at live help and they said, Oh, sorry I can't help) ANY IDEAS would be GREATLY appreciated!!

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