Hi @Deeg,
Seems your IIS 10 doesn't know how to serve files without extension, take a look to this post to let know IIS how to serve files without extension in acme-challenge dir.
This is the info shared by @JSpraul:
JSpraul
Feb '16I used GitHub - win-acme/win-acme: A simple ACME client for Windows (for use with Let's Encrypt et al.) with the following web.config in the acme-challenge directory to avoid a 404.17 IIS error ('The requested content appears to be script') blocking download of the challenge:
<?xml version="1.0" encoding="UTF-8"?> <configuration> <system.webServer> <staticContent> <mimeMap fileExtension="." mimeType="text/plain" /> </staticContent> </system.webServer> </configuration>
Cheers,
sahsanu