Dot Net SDK provided by Dropbox is not updated with TLS 1.2

Dropbox doesn't offer a step by step tutorial for this exactly, but perhaps you can elaborate on what you need to do at a high level, what you have so far, and what exactly isn't working.

For instance, in your first post you mentioned you needed to update your app from TLS 1.0 to 1.2. Does that mean you already had some working app/code? If so, while we recommend using the latest version of the SDK, it's not strictly required. Older versions of the same Dropbox .NET SDK can use TLS 1.2, without you changing your SDK/code, as long as your platform/framework itself supports it. In that case you may be able to update your platform/framework to support TLS 1.2 without needing to update your code itself or the version of the SDK you're using.

Also, I see you've spent some time looking at the examples for using the OAuth app authorization flow, but if this is only for your own use for connecting to your own account and you already had that connection working, via a long-lived access token (or short-lived access token and refresh token), for example, then you don't need to implement the OAuth app authorization flow now. (A TLS error would be unrelated to the access token you're using.)

Otherwise, feel free to share what you have so far and what exactly isn't working.

hi Thanks for your detail reply here is my code which was working fine before 13 Apr 2022

static string token = "sl.BGQcUuTPkIevMVmdApyqZuuAgXRn3lLOvhYlEroAFw4-Fb3Ez39x903gWSxFkR_m_tkq6CXU1Saz3IAc0qJtTb6hnhpb-r5C15WZ0W-lmBX6MKss7FOQ7k3z8VHivIWmuPyQTLk";
static void Main(string[] args)
{
para = args[0];
Myfolder = args[1];
actualpath = args[2];
PatientId = args[3];
ip = args[4];

var task = Task.Run((Func<Task>)Program.Run);
task.Wait();
Console.ReadKey();
}
static async Task Run()
{
using (var dbx = new DropboxClient(token))
{

//string file = actualpath;
string file = @"D:\testing.txt";
string folder = "/" + Myfolder;
// string filename = @"D:\testing.txt"; //para + ".pdf";
string filename = "testing" + ".txt";
string url = "";
using (var mem = new MemoryStream(File.ReadAllBytes(file)))
{
//try {
var full = await dbx.Users.GetCurrentAccountAsync();
var updated = dbx.Files.UploadAsync(folder + "/" + filename, WriteMode.Overwrite.Instance, body: mem);
updated.Wait();
var tx = dbx.Sharing.CreateSharedLinkWithSettingsAsync(folder + "/" + filename);
tx.Wait();
url = tx.Result.Url;
}

Console.Write(url);
}
}

and know i am getting following error

please let me know how can i remove this error.

Regards

I see you're getting an error "Could not create SSL/TLS secure channel.". That confirms that this is happening because Dropbox recently retired support for TLS 1.0 and 1.1. The Dropbox API servers now only support connections using TLS 1.2. You'll need to update your app/network client/environment to use TLS 1.2 in order to continue making Dropbox API calls.

I included some information about this in my first post in this thread. I've copied it here for reference:

By the way, I see you posted a (short-lived) access token here. While that particular access token would be expired by now, for future reference, as a matter of security, do not post your access token(s).