Title: Error – Addon unusable?
Last modified: March 7, 2018

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# Error – Addon unusable?

 *  [Stonehenge Creations](https://wordpress.org/support/users/duisterdenhaag/)
 * (@duisterdenhaag)
 * [8 years, 3 months ago](https://wordpress.org/support/topic/error-addon-unusable/)
 * I am trying to get this to work, but I get the following error as soon as I submit
   the form. Deactivating the Srout process rule will submit the form, but then 
   the addon is not used, of course.
 * Any suggestions?
    `Fatal error: Uncaught Error: Call to undefined method SI_Estimate_Submissions::
   __() in /home/stoneh1q/public_html/wp-content/plugins/caldera-forms-sprout-invoices-
   integration/cf-sprout-invoice.php:188 Stack trace: #0 /home/stoneh1q/public_html/
   wp-content/plugins/caldera-forms-sprout-invoices-integration/cf-sprout-invoice.
   php(119): cf_si_maybe_create_estimate(Array, 'fp_46424020') #1 /home/stoneh1q/
   public_html/wp-content/plugins/caldera-forms/classes/core.php(3192): cf_si_process_form_estimate(
   Array, Array, '_cf_process_5a9...') #2 /home/stoneh1q/public_html/wp-content/
   plugins/caldera-forms/classes/core.php(4882): Caldera_Forms::process_submission()#
   3 /home/stoneh1q/public_html/wp-content/plugins/caldera-forms/classes/core.php(
   3572): Caldera_Forms::process_form_via_post() #4 /home/stoneh1q/public_html/wp-
   includes/class-wp-hook.php(286): Caldera_Forms->cf_init_system('') #5 /home/stoneh1q/
   public_html/wp-includes/class-wp-hook.php(310): WP_Hook->apply_filters(NULL, 
   Array) #6 /home/stoneh1q/public_html/wp-includes/plugin.php in /home/stoneh1q/
   public_html/wp-content/plugins/caldera-forms-sprout-invoices-integration/cf-sprout-
   invoice.php on line 188`

The topic ‘Error – Addon unusable?’ is closed to new replies.

 * ![](https://ps.w.org/caldera-forms-sprout-invoices-integration/assets/icon-256x256.
   png?rev=989347)
 * [Caldera Forms - Sprout Invoices Integration](https://wordpress.org/plugins/caldera-forms-sprout-invoices-integration/)
 * [Frequently Asked Questions](https://wordpress.org/plugins/caldera-forms-sprout-invoices-integration/#faq)
 * [Support Threads](https://wordpress.org/support/plugin/caldera-forms-sprout-invoices-integration/)
 * [Active Topics](https://wordpress.org/support/plugin/caldera-forms-sprout-invoices-integration/active/)
 * [Unresolved Topics](https://wordpress.org/support/plugin/caldera-forms-sprout-invoices-integration/unresolved/)
 * [Reviews](https://wordpress.org/support/plugin/caldera-forms-sprout-invoices-integration/reviews/)

## Tags

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

 * 0 replies
 * 1 participant
 * Last reply from: [Stonehenge Creations](https://wordpress.org/support/users/duisterdenhaag/)
 * Last activity: [8 years, 3 months ago](https://wordpress.org/support/topic/error-addon-unusable/)
 * Status: not resolved