Title: Client Authentication failed
Last modified: April 3, 2023

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# Client Authentication failed

 *  Resolved [saadezz](https://wordpress.org/support/users/saadezz/)
 * (@saadezz)
 * [3 years, 2 months ago](https://wordpress.org/support/topic/client-authentication-failed-2/)
 * Hello,
 * I have got this error after activation the plugin>
   error: invalid_client
 * description: client authentcation failed.
   Im using smart buttonThanx
 * The page I need help with: _[[log in](https://login.wordpress.org/?redirect_to=https%3A%2F%2Fwordpress.org%2Fsupport%2Ftopic%2Fclient-authentication-failed-2%2F%3Foutput_format%3Dmd&locale=en_US)
   to see the link]_

Viewing 2 replies - 1 through 2 (of 2 total)

 *  Plugin Support [WebToffee Support](https://wordpress.org/support/users/webtoffeesupport/)
 * (@webtoffeesupport)
 * [3 years, 2 months ago](https://wordpress.org/support/topic/client-authentication-failed-2/#post-16627989)
 * Hi [@saadezz](https://wordpress.org/support/users/saadezz/),
 * Greetings from WebToffee support. The error message usually occurs due to the
   wrong PayPal API credentials.
 * To get the Client ID and Secret for the Smart buttons:
    - **Login **to your [PayPal business account ](https://www.paypal.com/in/signin).
    - Scroll down to the **REST API Integration **section and click **Manage API
      apps and credentials **. The **REST API apps **window opens up.
    - Go to **Activity **> **API Access **OR from **Account Settings **> **API Access**.
    - Click on the **PayPal Developer experience **link to create or manage apps.
    - Next, **Login to developer account **or **Signup a new developer account**.
      Click on the **Create a new application **or **default application **for your
      business account. Then, copy the **Client ID and Secret**.
    - Paste the **Client ID **and **Secret **in the respective fields of the plugin.
 * Let us know how it goes.
 *  Plugin Support [WebToffee Support](https://wordpress.org/support/users/webtoffeesupport/)
 * (@webtoffeesupport)
 * [3 years, 1 month ago](https://wordpress.org/support/topic/client-authentication-failed-2/#post-16650636)
 * Hi [@saadezz](https://wordpress.org/support/users/saadezz/),
 * This thread has been inactive for a while, so marking it as resolved.
 * Hope your problem is resolved. If you have further questions, please feel free
   to open a new topic.

Viewing 2 replies - 1 through 2 (of 2 total)

The topic ‘Client Authentication failed’ is closed to new replies.

 * ![](https://ps.w.org/express-checkout-paypal-payment-gateway-for-woocommerce/
   assets/icon-256x256.gif?rev=3385064)
 * [Payment Gateway of PayPal for WooCommerce](https://wordpress.org/plugins/express-checkout-paypal-payment-gateway-for-woocommerce/)
 * [Frequently Asked Questions](https://wordpress.org/plugins/express-checkout-paypal-payment-gateway-for-woocommerce/#faq)
 * [Support Threads](https://wordpress.org/support/plugin/express-checkout-paypal-payment-gateway-for-woocommerce/)
 * [Active Topics](https://wordpress.org/support/plugin/express-checkout-paypal-payment-gateway-for-woocommerce/active/)
 * [Unresolved Topics](https://wordpress.org/support/plugin/express-checkout-paypal-payment-gateway-for-woocommerce/unresolved/)
 * [Reviews](https://wordpress.org/support/plugin/express-checkout-paypal-payment-gateway-for-woocommerce/reviews/)

 * 2 replies
 * 2 participants
 * Last reply from: [WebToffee Support](https://wordpress.org/support/users/webtoffeesupport/)
 * Last activity: [3 years, 1 month ago](https://wordpress.org/support/topic/client-authentication-failed-2/#post-16650636)
 * Status: resolved