---
url: /zoho-payments-whmcs/errors.md
description: >-
  The exact messages Zoho Payments for WHMCS shows customers and records in the
  Gateway Log — license-inactive fallbacks, plus OAuth and webhook failure
  conditions.
---

# Error reference

This reference explains messages generated by Zoho Payments. Operational events are recorded in the **Gateway Log** (**Utilities → Logs → Gateway Log**).

## License messages

When a license is **inactive**, the gateway fails safely: new checkouts are suspended, but in-flight transactions are verified and applied.

| Where | Message | Meaning |
| --- | --- | --- |
| Customer, invoice page | *Online payment is temporarily unavailable. Please contact us to complete your order.* | The license is inactive, so a **new** payment cannot be started. |
| Gateway Log | *Payment blocked - license not active* | Recorded when a new payment is blocked (at most once an hour). |
| Gateway Log | *License Not Active - proceeding to verify/record payment* | A payment already made at Zoho is being **verified and recorded** even though the license is inactive — nothing is lost. |

To clear these, renew or re-enter your key — see [Licensing](/zoho-payments-whmcs/licensing).

## OAuth failure conditions

OAuth errors in the Gateway Log indicate authentication or token refresh failures:

* **Invalid credentials:** Client ID or Client Secret does not match the Zoho Developer Console app.
* **Redirect URI mismatch:** The authorized redirect URI is missing from the Zoho application configuration.
* **Revoked token:** The stored refresh token expired or was revoked; regenerate via the helper link.
* **Region mismatch:** Credentials belong to a different Zoho data centre than the configured **Data Center** (`IN` vs `US`).
  See [Troubleshooting → OAuth token errors](/zoho-payments-whmcs/troubleshooting#oauth-token-errors).

## Webhook failure conditions

Webhook events for Payment Links are rejected and logged under these conditions:

* **Signature mismatch:** **Webhook Secret** does not match Zoho's secret, failing HMAC-SHA256 validation.
* **Unreachable endpoint:** Webhook URL is invalid or lacks valid SSL, preventing delivery.
* **API verification failure:** Zoho API cannot verify the payment ID, leaving the invoice unpaid.
  See [Troubleshooting → Webhooks not processing](/zoho-payments-whmcs/troubleshooting#webhooks-not-processing).

## Related pages

* [Troubleshooting](/zoho-payments-whmcs/troubleshooting) — step-by-step fixes
* [Licensing](/zoho-payments-whmcs/licensing) — what the license gates and the fallback behaviour
* [Configuration](/zoho-payments-whmcs/configuration) — the fields these errors point to