Learn how to fix the “No ‘Access-Control-Allow-Origin’ header” CORS error in JavaScript by configuring CORS headers in Nginx, Apache, or Node.js. Web developers often encounter the dreaded CORS error while integrating APIs, scripts, or external resources across domains. A typical message looks like this: This error is one of the most common issues when working with web security and cross-domain communication. In this article, we’ll explore what causes this error, why browsers enforce it, and how to fix it properly across different server environments. What Is a CORS Error? CORS stands for Cross-Origin Resource Sharing. It’s a browser security mechanism…