Validation of the required challenges did not complete successfully. Invalid response

Good Morning,

I received a failure message attached below in the screenshot before when generating a SSL cert through http-01, I worked out the the clients domain name registrar is 1&1 and they do not allow external certificates using their name servers, so I verified with them if we use our name servers, it should work, so we have done so.

The website has now been over its 48hour window of propagation and I am receiving exactly the same error message, so would appreciate it if you could shed some light on why this is failing? All tests succeed when I click on the “Check” button.

error-ssl

Hi, I’ve replied to your support email now. Looks like a stray IP v6 AAAA record still pointing to an Apache server instead of your IIS.

Hi
I am encountering the same problem. There is no file access or file reading problems but the certificate creation is failing.
Regards
Terence

The most common reason for the cert creation to fail after a successful request is when your server time is not in sync. Try updating using an internet time server? Otherwise forward your logs to support at certifytheweb.com