Title: Fatal error after PHP Update
Last modified: May 25, 2024

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# Fatal error after PHP Update

 *  Resolved [jschachinger](https://wordpress.org/support/users/jschachinger/)
 * (@jschachinger)
 * [2 years ago](https://wordpress.org/support/topic/fatal-error-after-php-update-2/)
 * After an Update to PHP 8.3 I’m getting
 * **Fatal error: Uncaught Error: Undefined constant “CP_APPBOOK_DEFAULT_fp_from_email”**
 * when using the Plugin.
 * The page I need help with: _[[log in](https://login.wordpress.org/?redirect_to=https%3A%2F%2Fwordpress.org%2Fsupport%2Ftopic%2Ffatal-error-after-php-update-2%2F%3Foutput_format%3Dmd&locale=en_US)
   to see the link]_

Viewing 1 replies (of 1 total)

 *  Plugin Author [codepeople](https://wordpress.org/support/users/codepeople/)
 * (@codepeople)
 * [2 years ago](https://wordpress.org/support/topic/fatal-error-after-php-update-2/#post-17783619)
 * Hi,
 * You are using an outdated commercial version of the plugin. Please update to 
   the latest version to keep with compatible with PHP 8.x
 * If you need information about the update process for commercial versions, we’d
   like to help more but we can’t reply about that in this forum. We are not allowed
   to support any customers in these forums.
 * For pro or commercial product support please contact us directly on our site.
   Commercial products are [not supported in these forums](https://wordpress.org/support/guidelines/#do-not-post-about-commercial-products).
   We will happily answer this and any other questions you can have [on our own site](https://apphourbooking.dwbooster.com/contact-us).
 * Thank you!

Viewing 1 replies (of 1 total)

The topic ‘Fatal error after PHP Update’ is closed to new replies.

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## Tags

 * [fatal error](https://wordpress.org/support/topic-tag/fatal-error/)

 * 1 reply
 * 2 participants
 * Last reply from: [codepeople](https://wordpress.org/support/users/codepeople/)
 * Last activity: [2 years ago](https://wordpress.org/support/topic/fatal-error-after-php-update-2/#post-17783619)
 * Status: resolved