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Error message when trying to set up PRTG to use SSL on port 443. Running an IIS on the same server.



I have installed PRTG on a Windows 2008 R2 SP1 web edition machine with IIS 7.

In PRTG's Web Server setup (in PRTG Server Administrator), I try to select HTTP (Port 443) and from the Specify IPs list, I select an IP address that is not used by any of my websites. However, I still get the following error message when trying to save my settings:

None of the selected IPs could open port 443 which PRTG needs for SSL. Please specify at least one IP with port 443 open or deactivate the SSL option.

When running netstat -a on Windows command line, entries with port :443 appear in the list.

443 iis prtg ssl web-server

Created on May 16, 2011 1:21:25 PM by  Daniel Zobel [Product Manager]

Last change on May 16, 2011 1:30:36 PM by  Daniel Zobel [Product Manager]

3 Replies

Accepted Answer



This article applies to PRTG Network Monitor 8 or later

Free Port 443 for Use With PRTG's Web Server

In order to connect to PRTG's web server securely, you can set it to use https on port 443. In order for this to work, the port must not be occupied by any other application or service.

When running an IIS, it might (by default) listen on all IP addresses configured on the current machine, and therefore block port 443 for the address you're trying to use with PRTG.

In order to run PRTG side-by-side with a Microsoft Internet Information Service (IIS), please add all addresses actively used by your (non-PRTG) websites to the IP listen list, e.g. using the following command: netsh http add iplisten ipaddress=x.y.z.w

Additionally, make sure that none of the addresses you want to use with PRTG appears in the IP listen list. To show the list, you can use the following command: netsh http show iplisten

Once you made sure port 443 for the respective IP address is free, you can use it with PRTG.

UPDATE: Custom Port for PRTG SSL Web Server Available

You can now also configure PRTG to run on a port number different from 443. This can be an alternative solution when running a web server on the same machine..

As of version 12.3.4 [Stable] a custom SSL port for the PRTG web server can now be defined.

Quote from the version history:

Improved [Core]: PRTG web server can now run on https (SSL) on a user specific port (other than 443)

See Also

Why does PRTG block IIS SSL sites?

Created on May 16, 2011 1:52:45 PM by  Daniel Zobel [Product Manager]

Last change on Dec 3, 2012 2:18:42 PM by  Daniel Zobel [Product Manager]



So what if I am running Windows XP SP3 and getting this error? Also this box is running Rove Mobile software. When I try the netsh commands it says these are not valid.

Created on Oct 23, 2011 8:40:15 PM



if you stop the other web services and restart PRTG, does it work then?

Created on Oct 27, 2011 2:17:42 PM by  Aurelio Lombardi [Paessler Support]

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.