Why am I getting a 'User Authentication Failed' error with Payflow Pro?

[JZShah]

Hi,

I'm trying to integrate my payflow pro account. Enabled test mode, but getting the following error:

User Authentication Failed

Can anyone guide how this can be resolved.

One of the possible reasons is that Payflow Pro needs IP address to allow API to process payment. Can anyone tell me what is Shopify IP address that i can add to whitelist IPs to allow the transaction to happen.