Error in Calling HTTP Api in .net Framework

 

I am getting Above Error when i run that code on the server.

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Dim response As String = String.Empty

Dim MyRetVal As String = "Invalid"

Dim requestTOService As System.Net.HttpWebRequest

Dim auth_userid As Int64 = 377686

Dim api_key As String = "AdvY0zXBg9hNnqqXXuaPZLEXfIcDYUCb"

Try

System.Net.ServicePointManager.ServerCertificateValidationCallback = (Function(sender, certificate, chain, sslPolicyErrors) True)

ServicePointManager.MaxServicePointIdleTime = 1000

ServicePointManager.UseNagleAlgorithm = True

ServicePointManager.Expect100Continue = True

ServicePointManager.CheckCertificateRevocationList = True

ServicePointManager.DefaultConnectionLimit = _

ServicePointManager.DefaultPersistentConnectionLimit

requestTOService = System.Net.HttpWebRequest.Create("https://httpapi.com/api/domains/available.xml?auth-userid=" + auth_userid.ToString() + "&api-key=" + api_key + "&domain-name=" + MyDomain + "&tlds=" + tld)

requestTOService.Method = System.Net.WebRequestMethods.Http.Get

requestTOService.ContentType = "application/x-www-form-urlencoded"

requestTOService.KeepAlive = False

Dim responseFromService As System.Net.HttpWebResponse

responseFromService = CType(requestTOService.GetResponse(), System.Net.HttpWebResponse)

Dim readResponse As New System.IO.StreamReader(responseFromService.GetResponseStream())

response = readResponse.ReadToEnd

'ReadResponse

If response.Contains("available") Or response.Contains("Available") Then

MyRetVal = "available"

End If

Catch ex As WebException

If ex.Response IsNot Nothing Then

Dim httpwebres As System.Net.HttpWebResponse = ex.Response

Dim respSteam As New StreamReader(httpwebres.GetResponseStream())

 

End If

 

End Try

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