IWhen I go to change the email address and API credentials in the PayPal Payments Pro section of the config I get a message "The configuration has been saved." but the credentials have not actually been changed.
I'm lost as to why it will not change the credentials.
You should use Log feature of Magento to check your problem. You can enable this feature in your backend->System->Configuration->Developer->Log Settings and select Enabled as Yes. After that, if your site meet any problem, you can view it in the file system.log or exception.log in folder var/log on your server.
Hope this helpful for you.
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