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C# WebClient throws error while downloading a URL String

C# WebClient throws error while downloading a URL String

Guest User

9y19.2kLearn iOS Programming

Hi,

A URL was working fine for last many months but suddenly stops working in C# but the same URL is working in Excel VBA using MSXML2.XMLHTTP60 request.

I tried Webclient and HTMLAgility but both fails in dowloading string from a web URL

private void webClienttry()

{

WebClient webClient = new WebClient();

string result = webClient.DownloadString("https://www.komplett.no/category/10448/tv?subcategory=11157_TV-er&hits=200");

Console.WriteLine(result);

}

Error:

System.Net.WebException: 'The underlying connection was closed: An unexpected error occurred on a send.'

IOException: Unable to read data from the transport connection: An existing connection was forcibly closed by the remote host.

Can anyone help me finding the cause of error.

Thanks

Regards/Sachin

5 Replies

Know the answer? Post it — somebody with the same question will find it here.

Robert Raboud9y ago
Accepted answer
TLS 1.0 is now disable by default

try the code below

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

using (WebClient webClient = new WebClient())

{

string result = webClient.DownloadString("https://www.komplett.no/category/10448/tv?subcategory=11157_TV-er&hits=200");

Console.WriteLine(result);

}
Atta Kumah6y ago
Thnks Very Much working Fanstatic
Uwe Keim8y ago
To add to Robert's answer:

Starting from .NET 4.7, there is a new enum member SecurityProtocolType.SystemDefault which should be the best option to set (or not set it at all, since it is the default).

https://docs.microsoft.com/en-us/dotnet/api/system.net.securityprotocoltype?view=netframework-4.7
Dao Huong8y ago
Perfect Solution!
Johnson A8y ago
HI Robert Raboud,

You are my saviour. I spent days and days to figure out this.

your solution has answered me.

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

Thank you Thank you