If you are using Cloudflare to protect your Website and you are getting the Error "Webserver is returning an unknown error", it means that someone is attacking your IP behind Cloudflare, causing the DDoS Protection to enable.
To resolve this, please delete your A Record for your Domain:

and add an AAAA Record with your IPv6 address listed in our Plesk Panel, like this:


If you successfully followed these steps, your Website should work again!

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