Ensure the first two digits of your Syncfusion NuGet package version (e.g., 25 .x.x) match the version of the key you generated.

Once you've made your selections, click , and your key will be generated.

When upgrading packages, ensure all referenced Syncfusion NuGet packages are on the same version as your license key. Mixed versions often cause "invalid license key" errors. .

Do not put the key in appsettings.json directly. Use User Secrets for development and Environment Variables for production.

Hard-coding your license key directly in source code is a security risk. It can be exposed through compiled assemblies or inadvertently committed to version control.

Syncfusion provides one of the most comprehensive suites of enterprise-ready UI components for .NET, JavaScript, Flutter, and more. However, to move from a trial version to a fully licensed production environment, you must generate and register a correctly. Many developers face cryptic “Trial Expired” exceptions or license validation errors simply because they missed a step.

Hardcoding keys in your source code is a common but risky practice that can expose your license to unauthorized users. Follow these professional standards instead: Storing licensing key best practices | Others - Syncfusion