If you get error code 10002 using PayPal’s APIs, it's usually because of incorrect API Credentials or API permissions for third-party calls.
Third-Party API Calls
To allow a third-party to make API calls on your behalf, you must grant them permission. If you've already done this but got error code 10002, your shopping cart configuration may be the cause. Your shopping cart provider needs to know the primary email address on the PayPal account for which they're making the third-party API call, and they must add this email address to the API script.
If you're making third-party API calls but not using a shopping cart provider and you still get this error, it can be because of the following reasons:
- Incorrect API information - To retrieve the correct information, see Request API Credentials.
- Passing a value in the Subject field - This field should be blank if you're not making an API call on behalf of another person.
See the Developer Portal for a complete list of NVP/SOAP API error codes.
PayPal NVP and SOAP API Reference Guides.