I am having an issue when downloading a file from a https connection.
Everything works as expect for a while. Then after a seemingly random (although short) interval the downloads start failing with the following exception:
The underlying connection was closed: Could not establish trust relationship for the SSL/TLS secure channel. ---> System.Security.Authentication.AuthenticationException: The remote certificate is invalid according to the validation procedure.
The ca (Go Daddy) is trusted. It works for a dozen or so downloads and then gets this error. Once the error starts happening only a restart of the service doing the downloads will make it work again. Of course that functioning is short lived.
The code doing the download is dead simple :
private void DownloadFileTo(string targetPath)
{
using (WebClient client = new WebClient())
{
string finalURL = CombineURLParts();
client.DownloadFile(finalURL, targetPath);
}
}
I am tearing my hair out trying to make this work. I have attempted to disable cert validation using ServicePointManager.ServerCertificateValidationCallback, but the error still occurs. I am logging the cert in the handler, but everything looks identical between the downloads that work, and the ones that do not.
Any ideas?
