Issuing/renewing Let’s Encrypt certificate on Plesk for Windows server fails: https://acme-challenge.localhost Invalid hostname in redirect target, must end in IANA registered TLD

Symptoms

• Let's Encrypt certificate for a particular domain in Plesk for Windows can not be renewed automatically with the error message below:

  Failed to renew certificate of domain 'example.com': Invalid response from https://acme-v02.api.letsencrypt.org/acme/authz-v3/13769068820.
  Details:
  Type: urn:ietf:params:acme:error:connection
  Status: 400
  Detail: Fetching https://acme-challenge.localhost:443/.well-known/acme-challenge/jhpl_titvpnxqcffch5s9semwhzx1ytmjnhnngeyqek:
  Invalid hostname in redirect target, must end in IANA registered TLD

• In the document root of the affected domain, there is the file .htaccess.

Cause

In IIS on the affected domain, the third party ISAPI filter "ISAPI_Rewrite 3" (Apache .htaccess mod_rewrite compatible module for IIS) is enabled.

Resolution

1. Log into Plesk.

2. Go to Domains > example.com > File Manager page and rename the file .htaccess.