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User interface Website



Hi there,

What should i disable or change first before editing the PRTG SITE NAME and DNS in Website of User interface? I can't change it, below is the error that im receiving.

Error(Bad Request) The validation of the data you entered has failed. •The web server port 80 is not available. Please stop or reconfigure the application that is occupying this port or select a different port.

The setting have not been changed.

Thank you in advance!! :)

dns-name prtg-sitename user-interface website

Created on Mar 1, 2019 2:39:39 PM

1 Reply

Accepted Answer



Hi bslampitoc,

Not totally sure but I think the following link might help you:


What I highly recommend as a follow sys-admin, please DO NOT use port 80 at all - disable it and only use port 443 with a proper certificate to encrypt the web traffic for your own security.

There are even passwords transmitted to PRTG in order to set it up right - you don't want to send those clear text, not even on your private LAN, if you can avoid it by any means.

Hope the link helps - if not - is this an existing installation or a new one?


Florian Rossmark


Created on Mar 4, 2019 3:55:40 PM

Disclaimer: The information in the Paessler Knowledge Base comes without warranty of any kind. Use at your own risk. Before applying any instructions please exercise proper system administrator housekeeping. You must make sure that a proper backup of all your data is available.