Error when refreshing dataset via REST API in VB.net

[Anonymous]

Hello,

I'm using the following code to trigger a dataset refresh via the REST API and VB.net:

      Dim redirectUri, resourceUri, authorityUri, clientID As String

        redirectUri = "https://dev.powerbi.com/Apps/SignInRedirect"

        resourceUri = "https://analysis.windows.net/powerbi/api"

        authorityUri = "https://login.windows.net/common/"

        Dim authContext As New AuthenticationContext(authorityUri, New TokenCache())

        clientID = My-Client-ID

        Dim authenticationResult As AuthenticationResult

        Try

            authenticationResult = Await authContext.AcquireTokenAsync(resourceUri, clientID, New Uri(redirectUri), New PlatformParameters(PromptBehavior.Auto))

            Dim s As HttpWebRequest
            Dim enc As UTF8Encoding
            Dim postdata As String

            s = HttpWebRequest.Create("https://api.powerbi.com/v1.0/myorg/groups/My-Workspace/datasets/My-Dataset/refreshes")

            s.Method = "POST"
            s.KeepAlive = True
            s.ContentLength = 0

            s.Headers.Add("Authorization", String.Format("Bearer {0}", authenticationResult.AccessToken))
            s.ContentType = "application/x-www-form-urlencoded"

            s.GetResponse()

        Catch ex As Exception
            MessageBox.Show(ex.Message)
        End Try

This used to work perfectly. However suddenly I started to get an error at .GetResponse ("Connection closed..."). Does anyone have an idea where the problem could be? I updated all the involved nuget packages but that didn't help.

Thanks for any help!

[Anonymous · Accepted solution]

In case anyone is having the same issue, I had to enable TLS 1.2 for the connection, which I did by adding this line in code:

System.Net.ServicePointManager.SecurityProtocol = System.Net.SecurityProtocolType.Tls12

Reference here and here.