Https gives ERR_CONNECTION_RESET in Fiddler as well as .NET

Question

Could anybody explain to me why typing this link in Chrome

https://secure.malindoair.com/MalindoAirCIBE/OnlineBooking.aspx

while Fiddler is running gives a ERR_CONNECTION_RESET error?

PLEASE NOTE:

1. I have successfully set up Fiddler to "Decrypt HTTPS Traffic" and use its own certificate for that. I can see traffic from other HTTPS websites. Only this domain is behaving strange.

2. I tried using HttpWebRequest class in .NET to request a simple GET for this link with no parameters and no headers, and I receive "The underlying connection was closed: An unexpected error occurred on a send." error, which is almost certainly that same ERR_CONNECTION_RESET from Chrome.

3. I have tried inserting all kinds of headers such as Keep-Alive (tried both true and false) in my GET request, to no avail.

4. I am not using any proxy when coding in .NET.

Any ideas?

Answer 1

I had this problem for all https-sites, and solved it by resetting the Fiddler certificates from the "Tools > Fiddler Options > HTTPS" dialog. After resetting the certificates it's important to re-install the Fiddler root certificate in Firefox and/or other software that doesn't use the OS certificate store if you want to debug https sites in it.

See also https://textslashplain.com/2015/10/30/reset-fiddlers-https-certificates/