It is required as part of the DirectPayment API request to pass the variable, IPADDRESS, when you capture the buyer's IP address from their browser.
Length constraints are 45 single-byte characters, including periods and colons. Check the IP address and make sure it is in the correct format:
- IPv4 example, 255.255.255.255
- IPv6 example, FDEC:0:0:0:0:BBFF:0:FFFF or zero-compressed, FDEC::BBFF:0:FFFF
- IPv4-mapped IPv6 example, 0000:0000:0000:0000:0000:FFFF:255.255.255.25 or zero compressed, : :FFFF:255.255.255.25
PayPal highly recommends passing the buyer's IP address to detect possible fraud.
See the Developer Portal for a complete list of NVP/SOAP API error codes.