If you coded an application using a mix of the PayPal REST API and the classic PayPal Merchant SDK, this post is for you.
Originally I had coded an application which used the PayPal REST API to to instigate a Payment, as the REST API is the recommended one to use. At the time of integration the REST API was not fully developed and didn’t contain all the features the classic SDK offered, and that I needed. Therefore, at a certain point in my application (to be exact, when the user is redirected from PayPal back to the website) I used the classic SDK for a GETEC call I needed to retrieve customers’ information.
So the picture: PayPal REST API to create the payment, and the classic SDK to get the payment details.
All this worked fine for a long time (a year maybe?) when at some point the classic SDK call started returning intermittent “internal errors”.
I went around in circles with PayPal MTS for a few frustrating weeks, who insisted the errors are all due to account risk factors or unavailable funds. Meanwhile the errors were happening more and more frequently.
I finally got someone who knows what they’re talking about, and figured out the errors are due to the fact that I was using the REST and classic API together.
Your specific errors appear to be related to a change in how we are processing different API requests. The update in platforms means that the GetEC calls are now routed through a different service, which has unintended results due to the hybrid integration.
After changing over to using the REST API only, everything worked fine.
Hope this helps.