In order to upgrade the license of GcExcel.NET to the latest version 2.2.0, you need to set a new license key (the new version doesn't work with the license keys of older versions). This is a free upgrade for existing customers who already have licensed version of GcExcel. The GrapeCity Sales team will provide existing users with the new license key via email.

After receiving the new license key, follow the steps shared below:

1. Open an existing .NET core application created with GcExcel.NET previous license.
2. Right-click the project in Solution Explorer and choose Manage Nuget Packages.
3. In the Package Source on top right, select nuget.org
4. Click Updates tab on the top to display the list of all the installed Nuget packages.
5. On the left panel, select the Select all packages check box and click Update.
6. In the Preview Changes dialog, click Ok and choose I Accept in the next screen.
7. Switch to the code view and replace the old key with the new license key received via email.
   • To upgrade the license of a particular instance:
     var doc = new GcExcelDocument(new key);
   • To upgrade the license of all the instances:
     GcExcelDocument.SetLicenseKey(new key);