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GitHub User: srdjan-cengic
For error: "This transaction cannot be processed due to an invalid merchant configuration."
Go to developer.paypal.com, register with your normal PayPal account, tab Applications than click on Sandbox Accounts, find your seller account click on him and hit profile.
Under profile tab change Account type to Business-Pro.
Just wanted to ask, cast is from 2009, is there any major changes to this today, or i can go to production with this solution without problems?