Can't get Oauth to work... please help

Hi Littlepage​ 

Thanks for sharing the code snippet. I tested it on my end and was able to successfully generate a valid authorization URL. I’d recommend double-checking your environment variables and ensuring that the correct values are being passed to their corresponding variables. That should help narrow down what might be happening.

Here's my complete code.. and I tried and it doesn't work

namespace LittlePageUpload3
{
    using Dropbox.Api;
    using System;
    using System.Diagnostics; // For Process.Start
    using System.Runtime.InteropServices;
    using System.Threading.Tasks;

    public partial class Program
    {
        static async Task Main(string[] args)
        {
            const string AppKey = "xtva8nnzc76bn1g"; // Replace with your App Key
            const string AppSecret = "XXXX"; // Replace with your App Secret
            const string RedirectUri = "http://localhost:8080/"; // Replace with your Redirect URI

            // Generate a unique state for security
            string oauth2State = Guid.NewGuid().ToString("N");

            // Get the authorization URI
            Uri authorizeUri = DropboxOAuth2Helper.GetAuthorizeUri(
                OAuthResponseType.Code, 
                clientId: AppKey,
                new Uri(RedirectUri),
                state: oauth2State,
                tokenAccessType: TokenAccessType.Offline 
                
            );

            // Open the URI in the user's default browser
            Console.WriteLine("Opening Dropbox authorization in your browser...");

            
            Console.WriteLine("authorizeUri: " + authorizeUri.ToString());
            Process.Start(new ProcessStartInfo("cmd", $"/c start {authorizeUri}") { CreateNoWindow = true });
            

            Console.WriteLine("Please authorize the app in your browser and copy the code from the redirect URL.");
            Console.Write("Enter the authorization code: ");
            string code = Console.ReadLine();

            // Exchange the authorization code for access and refresh tokens
            var tokenResult = await DropboxOAuth2Helper.ProcessCodeFlowAsync(
                code: code,
                appKey: AppKey,
                appSecret: AppSecret,
                redirectUri: RedirectUri
            );

            // Store tokenResult.AccessToken and tokenResult.RefreshToken securely
            Console.WriteLine($"Access Token: {tokenResult.AccessToken}");
            Console.WriteLine($"Refresh Token: {tokenResult.RefreshToken}");

        }
    }
}

My control panel looks like this:

The problem starts on the way we call the new browser window to open... here's the correct code:

// Corrected Process.Start usage

var processStartInfo = new ProcessStartInfo
{
    FileName = authorizeUri.ToString(),
    UseShellExecute = true
};
Process.Start(processStartInfo);

Hi Littlepage​ 

Thank you for that additional information.

I am still unable to replicate the error you originally reported: Missing client_id.

The full code you provided works without issues on my end.

Are you able to share the full authorization URL that your program is generating? Since you are logging it: Console.WriteLine("authorizeUri: " + authorizeUri.ToString());