Title: Uncaught ReferenceError: Backbone is not defined
Last modified: July 26, 2023

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# Uncaught ReferenceError: Backbone is not defined

 *  Resolved [myhappyidea](https://wordpress.org/support/users/myhappyidea/)
 * (@myhappyidea)
 * [2 years, 10 months ago](https://wordpress.org/support/topic/uncaught-referenceerror-backbone-is-not-defined-3/)
 * Suddenly my form is out of whack, not displaying items in order or the multiple
   parts the form has (it has 4 parts).
 * I can see it is giving me this error:
 * loadControllers.js:25 Uncaught ReferenceError: Backbone is not defined
   at loadControllers.
   js:25:1at main.js:28:1
 * I have no cache plugins installed.
 * The page I need help with: _[[log in](https://login.wordpress.org/?redirect_to=https%3A%2F%2Fwordpress.org%2Fsupport%2Ftopic%2Funcaught-referenceerror-backbone-is-not-defined-3%2F%3Foutput_format%3Dmd&locale=en_US)
   to see the link]_

Viewing 1 replies (of 1 total)

 *  [Shaylee](https://wordpress.org/support/users/shayleehansen30/)
 * (@shayleehansen30)
 * [2 years, 10 months ago](https://wordpress.org/support/topic/uncaught-referenceerror-backbone-is-not-defined-3/#post-16925021)
 * 
   Hello,
 * We apologize for the inconvenience you are experiencing with your form. The error
   you mentioned, “Backbone is not defined,” can occur due to a conflict with other
   plugins or themes on your website.
 * To troubleshoot and resolve this issue, we recommend the following steps:
    1. **Check for Plugin and Theme Conflicts: **Temporarily deactivate all other plugins
       and switch to a default WordPress theme (e.g., Twenty Twenty-One). Then, check
       if the issue persists. If the problem is resolved, it indicates that there was
       a conflict with one of the plugins or the theme. You can then reactivate the
       plugins and themes one by one to identify the specific one causing the conflict.
    2. **Clear Your Browser Cache: **Sometimes, browser caching can cause issues with
       how pages are displayed. Clear your browser cache and refresh the page to see
       if that resolves the problem.
    3. **Update Ninja Forms and Its Add-ons**: Ensure that you are using the latest
       versions of Ninja Forms and its add-ons. Outdated versions can sometimes cause
       compatibility issues.
    4. **Check JavaScript Errors:** Use your browser’s developer tools to check for
       any additional JavaScript errors on the page. This can provide further insights
       into the cause of the issue.
    5. **Verify Form Settings:** Double-check the form settings to ensure that the 
       multiple parts are correctly configured. Make sure each part is enabled and 
       arranged in the desired order.
 * If the issue persists after trying these steps, please reach out to our [Customer Success team](https://ninjaforms.com/contact).
   As they are dedicated to helping you resolve any problems and ensure your form
   is working as expected.

Viewing 1 replies (of 1 total)

The topic ‘Uncaught ReferenceError: Backbone is not defined’ is closed to new replies.

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 * 1 reply
 * 2 participants
 * Last reply from: [Shaylee](https://wordpress.org/support/users/shayleehansen30/)
 * Last activity: [2 years, 10 months ago](https://wordpress.org/support/topic/uncaught-referenceerror-backbone-is-not-defined-3/#post-16925021)
 * Status: resolved