VB.NET 401 Unauthorized error in PayPal OAuth API-CodePudding

I'm trying to get an access token back from PayPals OAuth API, I can get it back with curl but need to get the code through vb.NET. I always get a 401 unauthorized response but can't see why. I'm using the following code:

Dim uri as new Uri("https://api-m.sandbox.paypal.com/v1/oauth2/token")
    Dim wClientID As String = "client ID"
    Dim wClientSecret As String = "Client Secret"
    Dim data as string = "grant_type=client_credentials"
    Dim dataByte as Byte()
    
    ServicePointManager.Expect100Continue = true
    ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12

    request = WebRequest.Create(uri)
    request.Headers.Add("Username", wClientID)
    request.Headers.Add("Password", wClientSecret)
    request.Headers.Add(HttpRequestHeader.Authorization, "Basic " & wClientID & ":" & wClientSecret)
    request.ContentType = "application/x-www-form-urlencoded"
    request.Method = "POST"
    
    dataByte = Encoding.UTF8.GetBytes(data)
    
    Using requestStream = request.GetRequestStream
        requestStream.Write(dataByte, 0, dataByte.Length)
        requestStream.Close()
    End Using

Any help would be appreciated, I've triple checked the client id and secret, both are definitely correct

CodePudding user response：

You need to Base64 encode the clientid:secret string for HTTP basic authentication. Curl does this for you.