The error message "Uncaught ReferenceError: jQuery is not defined" typically occurs when the DataTables library is being loaded before jQuery or when jQuery is not being loaded at all.

Here's how you can resolve the issue:

Ensure jQuery is Loaded First:

• Make sure that jQuery is loaded before DataTables and any other libraries that depend on it.
• Check your HTML code or layout file to ensure that the jQuery script tag is included before the DataTables script tag.
• Example:

<script src="https://code.jquery.com/jquery-3.6.0.min.js"></script>
<script src="https://cdn.datatables.net/1.11.5/js/jquery.dataTables.min.js"></script>

Check for Conflicting Scripts:

• Make sure there are no other scripts that might conflict with jQuery or DataTables.
• Check for any other libraries or custom scripts that might be manipulating the jQuery namespace or causing conflicts.

Verify CDN URLs:

• Ensure that the CDN URLs for jQuery and DataTables are correct and accessible.
• Sometimes CDN URLs may change, so double-check the documentation or the CDN provider's website for the latest URLs.

Check Browser Console Errors:

• Inspect your web page using browser developer tools (usually accessible via F12 or right-click -> Inspect) and check for any additional error messages related to script loading or execution.

Fallback to Local Scripts:

• If CDN links are not working, consider downloading the jQuery and DataTables files and hosting them locally in your project.
• Update the script tags in your HTML to reference the local files.

Use jQuery.noConflict():

• If you're using other libraries that might conflict with jQuery's $ alias, consider using jQuery.noConflict() to release the $ alias.
• Example:

jQuery.noConflict();
(function($) {
    // Your jQuery code using $ alias
})(jQuery);

By following these steps, you should be able to resolve the "jQuery is not defined" error and get DataTables working properly in your project.

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