Why SSL verification of my domain name failed?

[JuergenAuer]

Hi @TonySSL

@TonySSL

I am able to access file in the diretory.

http://www.friendly.cool/.well-known/acme-challenge/test.htm

remove the .html extension.

The file Letsencrypt checks is extensionless. So a file with .htm may work, a file without not.