GPCB PAY / INTEGRATION GUIDE

Integration Documentation.

Connect your WooCommerce store to GPCB Pay, configure your merchant account, and understand the supported PayPal-powered card payment experiences.

01 WooCommerce Store Checkout
02 GPCB Pay SaaS Private Payment Core
03 PayPal Payment Provider
01 / INTRODUCTION

What Is GPCB Pay?

GPCB Pay is an independent WooCommerce payment integration built around two components: a lightweight WooCommerce Connector and a private SaaS Payment Core.

The Connector integrates with WooCommerce checkout and communicates with the SaaS through authenticated server-to-server requests.

The private SaaS coordinates payment initialization, PayPal order creation, verified capture, idempotency, and durable payment recovery.

Architecture principle

WooCommerce remains the authority for the commercial order. GPCB Pay SaaS manages trusted payment operations. PayPal remains the payment provider.

02 / BEFORE YOU BEGIN

Requirements

Before connecting your store, make sure the following requirements are satisfied.

  • An operational WordPress website with WooCommerce installed and configured.
  • HTTPS enabled for your storefront and checkout.
  • Administrator access to WooCommerce payment settings.
  • A GPCB Pay merchant account with a verified email address.
  • A store you own or are authorized to manage.
  • Valid Connector credentials issued through the GPCB Pay onboarding process.
  • A PayPal Business account with suitable credentials and supported payment capabilities.
Important

Creating a merchant account, verifying a store connection, and enabling production payments are separate steps. PayPal eligibility and SaaS payment authorization must also be satisfied.

03 / WOOCOMMERCE

Install the Connector

GPCB Pay uses a lightweight WooCommerce plugin to connect your store with its private SaaS payment infrastructure.

01

Open WordPress Admin

Sign in to your WooCommerce website using an authorized administrator account.

02

Install the Plugin

Open Plugins, select Add New Plugin, and use Upload Plugin if you have received the official Connector package.

03

Activate the Connector

Activate the plugin, then open its payment gateway configuration under WooCommerce payment settings.

04

Configure Your Connection

Enter the Connector credentials issued for your store, select the intended environment, and save your settings.

05

Verify and Activate

Follow the new-store connection verification process and complete the remaining activation requirements in the Merchant Dashboard.

Plugin distribution

Use only the official GPCB Pay distribution channel. Public WordPress plugin availability is separate from access to the private SaaS service. Installing the Connector does not automatically authorize payment processing.

04 / MERCHANT ONBOARDING

Connect Your Store

The Merchant Dashboard manages your account, store onboarding, PayPal connection, and subscription information. WooCommerce manages the local Connector configuration.

  1. Create an account. Register through the GPCB Pay Merchant Portal.
  2. Verify your email. Complete email verification before continuing with protected account actions.
  3. Add your store. Sign in, open My Stores, and start the available WooCommerce store onboarding workflow.
  4. Configure the Connector. Obtain the credentials issued for your store, enter them in WooCommerce, and save the settings.
  5. Verify New Store Connection. Use the new-store verification action in WooCommerce. This checks the pending Connector relationship; it does not activate the store.
  6. Complete store activation. Return to the Merchant Dashboard and follow the required ownership, domain, and activation instructions.
  7. Test Active SaaS Connection. Once the SaaS confirms that the store is active, use Test SaaS Connection in WooCommerce.
  8. Connect PayPal Business. Enter the appropriate PayPal Client ID and Client Secret through the secure Merchant Dashboard workflow.
  9. Complete payment readiness. Follow the available Live readiness, eligibility, and subscription or trial authorization steps.
Two different connection checks

Verify New Store Connection is intended for a store that is still being provisioned. It produces temporary connection evidence for onboarding.

Test SaaS Connection is intended for an already active store. A successful test does not independently authorize Live payments or activate a subscription.

Complete activation promptly

Pending connection proof is time-limited. Follow the validity information shown during onboarding and complete the required activation steps before the proof expires. If it expires, repeat the supported verification process.

05 / CONNECTION SETTINGS

Connector Configuration

The WooCommerce Connector authenticates server-to-server requests using credentials associated with your authorized SaaS store.

Setting Purpose
Connector Key ID Identifies the issued Connector credential.
Connector Signing Secret Authenticates signed requests between WooCommerce and the SaaS. Keep it private.
Environment Selects the intended Sandbox or Live payment environment.
Payment Mode Selects the configured Guest or eligible Advanced Card experience.

The SaaS derives store identity from authenticated Connector credentials. Browser-supplied merchant identifiers do not establish payment authority.

Connector credentials are not PayPal credentials

Connector credentials authenticate your WooCommerce store with GPCB Pay SaaS.

PayPal Client ID and Client Secret belong in the secure PayPal connection workflow inside the Merchant Dashboard, not in the WooCommerce Connector settings.

Protect your credentials

Never place Connector signing secrets, PayPal Client Secrets, passwords, or server access tokens in public HTML, JavaScript, support messages, or screenshots.

06 / PAYPAL INTEGRATION

Payment Modes

GPCB Pay supports two PayPal-powered card payment integration paths. Availability is determined by PayPal requirements, merchant eligibility, and checkout context.

MODE 01

Guest Card Payments

Provides a supported PayPal-hosted guest card payment experience within the WooCommerce checkout flow. Availability depends on PayPal and the specific merchant and checkout context.

MODE 02

Advanced Card Payments

Uses PayPal-hosted Card Fields for merchants specifically eligible and approved for Advanced Card Payments. This capability is not available to every PayPal account.

Payment eligibility

A successful Sandbox integration does not guarantee Live availability. Advanced Card Payments require applicable PayPal merchant approval. Guest Card availability also depends on PayPal requirements.

07 / PAYMENT CORE

Payment Lifecycle

GPCB Pay separates WooCommerce commercial authority from trusted payment operations.

01

Checkout Initialization

WooCommerce prepares the trusted order amount, currency, reference, and commercial context.

02

PayPal Order Creation

The Connector sends an authenticated request to the SaaS. The Payment Core persists durable request identity before the provider operation.

03

Payment Approval

The buyer completes the applicable PayPal-supported payment experience. Approval alone does not mark the WooCommerce order as paid.

04

Verified Capture

The trusted server-side capture flow validates the provider result against the expected payment identity, amount, and currency.

05

WooCommerce Completion

WooCommerce records successful payment only after the Connector validates the verified capture evidence returned by the SaaS.

Payment authority

Neither a browser success message nor a PayPal approval event is sufficient to finalize a WooCommerce payment.

08 / PAYMENT RELIABILITY

Idempotency & Recovery

Payment requests can be interrupted by network failures, delayed provider responses, or repeated checkout actions.

GPCB Pay uses durable payment state and persisted request identifiers to support controlled retries and recovery.

  • Durable PayPal Create request identifiers.
  • Durable Capture request identifiers.
  • Payment identity checks during recovery.
  • Server-side capture verification.
  • Protection against conflicting or duplicate payment transitions.
  • Controlled recovery for compatible interrupted attempts.
What happens if the GPCB Pay service is unavailable?

GPCB Pay requires its private SaaS Payment Core to coordinate payment operations. If the service is unavailable before payment creation, checkout cannot complete a payment through GPCB Pay.

The Connector must not mark an order as paid without trusted, verified capture evidence. A service interruption is not proof that a payment succeeded or failed.

Interrupted or uncertain payment results

If a connection is lost after a payment operation has been submitted, the payment outcome may remain uncertain until the original attempt can be verified.

A PayPal capture may have completed even if WooCommerce did not receive its final confirmation. Do not assume the payment failed or initiate another capture solely because a response was interrupted.

Supported recovery uses existing payment identity and trusted provider verification. Some cases may require reconciliation or assistance from GPCB Pay support. Automatic recovery is not guaranteed for every interruption.

Important payment rule

Do not manually repeat payment captures outside the supported workflow. A pending or interrupted payment must be resolved through trusted payment state and verification.

09 / COMMERCIAL ACCESS

Subscription & Trial

GPCB Pay offers one Pro plan with two published billing periods. Both provide access to the same supported Pro capabilities.

PRO MONTHLY

$19 / month

Monthly access for one authorized WooCommerce website, subject to confirmed subscription payment and valid entitlement.

PRO YEARLY

$190 / year

Annual access for one authorized WooCommerce website, subject to confirmed subscription payment and valid entitlement.

Eligible merchants may qualify for one seven-day trial. The trial begins only after the required store activation, Live payment readiness, and separate SaaS trial authorization.

Registration alone does not start the trial. An activated trial lasts 168 consecutive hours. Subscription renewal is manual, not automatic.

Public billing availability

Published prices are informational while public subscription checkout is being prepared. Payment admission, trial authorization, and paid subscription entitlement are independently controlled by the SaaS.

Creating an account or completing store verification does not automatically activate paid access.

What Happens When My Trial or Subscription Expires?

Connector installation: Expiration does not automatically uninstall or deactivate the GPCB Pay WooCommerce Connector. The plugin remains installed unless you remove or deactivate it yourself.

New payments: When SaaS subscription admission enforcement applies, an expired trial or paid access period cannot authorize new payment creation. New payment attempts require valid access under the applicable authorization rules.

Existing WooCommerce orders: Expiration alone does not automatically cancel existing orders or change their status to Paid, Failed, or Cancelled. Order status continues to depend on the relevant WooCommerce and verified payment evidence.

Existing payment attempts: Payment attempts created before expiration are not automatically treated as successful or failed. Their recorded state, payment identity, and available provider evidence determine the applicable verification, capture, recovery, or reconciliation process.

Manual renewal: GPCB Pay does not automatically renew subscriptions or make recurring subscription charges. Merchants must complete the applicable manual renewal process to obtain a new paid access period.

10 / SUPPORT RESOURCES

Troubleshooting

What is the difference between Verify New Store Connection and Test SaaS Connection?

Verify New Store Connection is used during initial store provisioning. It establishes temporary connection evidence. Test SaaS Connection checks an already active store. Neither action independently authorizes payment processing.

Why did my connection proof expire?

New-store connection evidence has a limited validity period. If the proof expires before activation, repeat the supported verification step and follow the Merchant Dashboard instructions.

Why is my store not active?

Store provisioning, Connector verification, domain ownership verification, and activation are separate operations. Review the outstanding requirements in My Stores.

Why did domain verification fail?

Confirm that the verification record matches the exact instructions shown for your store. DNS changes may require time to propagate. Do not modify unrelated DNS records.

Where do I enter PayPal credentials?

Enter your PayPal Business Client ID and Client Secret through the secure Merchant Dashboard PayPal connection workflow. Do not place PayPal Client Secrets in the WooCommerce Connector.

Why was my PayPal connection rejected?

Check the selected environment, merchant account, and credential accuracy. PayPal account permissions and supported capabilities may also affect connection readiness. Never send secrets to support.

Why are Advanced Card Fields unavailable?

Advanced Card Payments require applicable PayPal merchant eligibility and approval. Sandbox success does not guarantee Live availability.

Why has my trial not started?

Registration and store verification do not automatically start a trial. The required activation, Live payment readiness, and separate trial authorization must be completed.

Why is subscription checkout unavailable?

Public billing checkout is independently controlled by the SaaS. Published prices do not indicate that public checkout is currently enabled.

Why is my WooCommerce order not marked paid?

GPCB Pay requires successful server-side capture verification. PayPal approval alone is insufficient. Review the authorized WooCommerce order status and relevant payment information. Contact support if the outcome remains uncertain.

Can I retry an interrupted payment?

The Payment Core supports controlled recovery for compatible durable payment attempts. Do not manually issue repeated captures outside the supported integration workflow.

What happens if GPCB Pay SaaS is down?

GPCB Pay depends on its private SaaS Payment Core. If the service is unavailable, new payments through GPCB Pay may be unable to complete. The Connector must not mark an order as paid without verified capture evidence.

If an operation was already submitted, its result may require verification after connectivity returns. Do not assume that a timeout means the payment failed.

What should I do if a payment appears successful in PayPal but remains pending in WooCommerce?

Do not submit another capture or manually mark the order paid based only on a browser message. Check the order and available PayPal transaction information, then contact GPCB Pay support if the records remain inconsistent.

Provide the WooCommerce Order ID, approximate transaction time, and a description of the issue. Never send card data, passwords, or integration secrets.

11 / SECURITY MODEL

Security Principles

GPCB Pay is designed around authenticated server boundaries, trusted commercial authority, and verified payment evidence.

  • Merchant and store identities are established through trusted authentication.
  • Connector requests use authenticated server-to-server communication.
  • Browser input cannot independently authorize payment capture.
  • Payment amounts and currencies originate from trusted WooCommerce commercial assertions.
  • PayPal merchant secrets remain within protected SaaS backend workflows.
  • Durable payment operations use persisted state and idempotency safeguards.
  • WooCommerce payment completion requires verified capture evidence.
Where does customer card data go?

Supported card-entry experiences use PayPal-hosted payment interfaces. Card details are entered through PayPal-provided payment components rather than custom GPCB Pay card-entry forms.

The WooCommerce Connector and GPCB Pay SaaS Payment Core are not designed to receive or store buyers' complete card numbers or CVV values.

GPCB Pay processes payment references, trusted order information, and provider responses required to coordinate and verify payments. PayPal remains the payment provider responsible for its hosted card-entry experience.

Merchant security responsibilities

Merchants remain responsible for securing their WordPress website, administrator accounts, WooCommerce installation, and authorized access to the GPCB Pay Merchant Dashboard.

Do not collect or transmit complete payment card details through custom forms, support requests, screenshots, or unrelated plugins.

GPCB Pay does not bypass PayPal eligibility rules, merchant approval requirements, or applicable payment provider restrictions.

12 / GET HELP

Need Help Integrating?

For Connector configuration, merchant onboarding, PayPal eligibility, payment troubleshooting, or billing questions, contact GPCB Pay support.

Reporting a payment issue

First review the WooCommerce order status and any available payment information. If the payment outcome remains unclear, contact support before attempting another payment capture.

Include your store domain, WooCommerce Order ID, approximate transaction time, payment environment, and a short description of what happened. You may include non-sensitive error references when available.

If PayPal shows a completed transaction while WooCommerce remains pending, explain that difference in your support request. Do not manually change the order to paid without resolving the payment evidence.

OFFICIAL SUPPORT

support@gpcbpay.com

Never include card numbers, passwords, PayPal Client Secrets, Connector signing secrets, or private access tokens in support messages.

Contact Support