Resolving the Token 2001530 Is Not Valid Error in NET MAUI

Today, Monday, I encountered a new bug that appeared after switching between two branches—one targeting Xamarin.Forms and the other .NET MAUI. While I was able to build the .NET MAUI app for Android, the iOS build crashed in AppDelegate with the following error:

System.ArgumentOutOfRangeException: Token 2001530 is not valid in the scope of module Microsoft.iOS.dll. (Parameter 'metadataToken')

This error was caught and logged, revealing an issue in the Main method of the iOS application:

public class Application
{
    private static void Main(string[] args)
    {
        try
        {
            UIApplication.Main(args, null, typeof(AppDelegate));
        }
        catch (Exception ex)
        {
            Console.WriteLine(ex);
            FileLogger.MakeSureAllLogsAreWritten();
            throw;
        }
    }
}

The error message suggested that an incorrect or outdated version of a library was being referenced. This kind of issue is often resolved by following these steps:

1. **Manually remove** the `bin` and `obj` folders.
2. Run a **NuGet restore**.
3. **Rebuild** the project.

Sure enough, after following these steps, the app built successfully. Hopefully, this quick fix helps anyone else encountering this error!

Resolving the Token 2001530 Is Not Valid Error in NET MAUI

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