To test payment operations, you need to create test users (seller and buyer(s)).
To create them, you must setup your credentials with your MercadoPago account (not test account).
Then, you need to call the CreateTestUser procedure, located at Root -> MercadoPago -> Users. This procedure will return a &UserTestSDT SDTwith all the information about the user, which can be saved to your local Database (you can run the TestCreateTestUser Command Line procedure under Sample folder to see the result)
&siteId = site_id.Uruguay
MercadoPago.Users.CreateTestUser(&siteId,&UserTestSDT,&Message,&ErrorCode)
To be able to use one of those as the seller, you need to set up the credentials (in the GetCredentials Procedure) with one of the test users' credentials (the one you want to use as the seller), as they are required to get an Access Token, required by various API functionalities. (see Get MercadoPago Credentials)
Notes:
- If you just got your user credentials, you need to log out from MercadoPago and log in with the test user.
- It is recommended to store your credentials in your Database, as you may need them later.