Title: CRITICAL Uncaught Error: Call to undefined function GuzzleHttp\json_encode()
Last modified: January 23, 2024

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# CRITICAL Uncaught Error: Call to undefined function GuzzleHttp\json_encode()

 *  [MyWorks](https://wordpress.org/support/users/myworksdesign/)
 * (@myworksdesign)
 * [2 years, 4 months ago](https://wordpress.org/support/topic/critical-uncaught-error-call-to-undefined-function-guzzlehttpjson_encode/)
 * We’re seeing the below PHP error occurring when using another plugin that also
   uses the Guzzle library when ActiveCampaign is installed. Upon further troubleshooting,
   this seems to be the result of the Guzzle library in the ActiveCampaign plugin
   not being updated to a recent/latest version?
 * `CRITICAL Uncaught Error: Call to undefined function GuzzleHttp\json_encode()`

The topic ‘CRITICAL Uncaught Error: Call to undefined function GuzzleHttp\json_encode()’
is closed to new replies.

 * ![](https://ps.w.org/activecampaign-for-woocommerce/assets/icon-256x256.png?rev
   =1925389)
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 * 0 replies
 * 1 participant
 * Last reply from: [MyWorks](https://wordpress.org/support/users/myworksdesign/)
 * Last activity: [2 years, 4 months ago](https://wordpress.org/support/topic/critical-uncaught-error-call-to-undefined-function-guzzlehttpjson_encode/)
 * Status: not resolved