When testing some donations on my local machine, I set various key=value pairs to do various things (return to specific thank you page, get POST data from PayPal and not GET data and others) I also built my code around the response from the PayPal sandbox.

BUT, when my code goes to the production server and we switch on live payments and test with real accounts and money, a few strange things happen;

1. We get a GET response from PayPal - the URL is filled with crap.
2. We get no transaction details. This is the biggie, no name, no txn_id, no dates, nothing. We get a handful of keys etc, its not totally empty and the payment has gone through, but nowhere near the verbosity of the sandbox.

Curious about why this might be? It doesn't really make sense to have a sandbox (or dev environment) that is substantially different from the production environment. Or, am I missing something?

EDIT: Still no response to my question in the PayPal Developer Forums. I don't even get a donation amount back from PayPal. Is this a setting maybe?

EDIT #2: Two of you have suggested to check PDT and Auto-Return. The data analytics guy for the project only 2 hrs ago suggested the same. I have asked the client to confirm this. I can't see a setting for it in the Sandbox so can assume that it is enabled by default?