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SSL Cert for PRTG



I have followed the instructions to setup an SSL certificate for PRTG (https://kb.paessler.com/knowledgebase/en/topic/283-how-can-i-use-a-trusted-ssl-certificate-with-the-prtg-web-interface#reply-713), however when starting the PRTG Core Server Service we get an error... Could not start webserver for Tried to start Web server for configured IP/port Setting:Could not load key, check password. Tried to start web server for IP and port 80/443(SSL) - failed: Could not load key, check password.

Any suggestions? FYI, we are using a wildcard certificate that had been generated for an IIS server.

check-pasword core-server could-not-load-key ssl

Created on Feb 24, 2012 6:20:47 PM

3 Replies

Accepted Answer



Dear Bill,

when using SSL, PRTG can only run on port 443. Please make sure you configured the PRTG core server accordingly (see PRTG Server Administrator: Web Server).

Also, please make sure you provide the prtg7.key file in decrypted format. PRTG's web server cannot handle key files that are still encrypted.

Certificate (prtg7.crt) and root certificate (root.pem) must both be provided in PEM encoded format. If you need to convert files, the following tools might be of some help: http://www.sslshopper.com/ssl-certificate-tools.html

Created on Feb 27, 2012 1:10:12 PM by  Daniel Zobel [Product Manager]

Last change on Feb 27, 2012 1:12:41 PM by  Daniel Zobel [Product Manager]



We are choosing port 443, not sure why it is reporting 8080. I went through the sslshoppeer.com tools and confirmed that our certificates match and that they are in PEM format. I followed the steps that I linked to on my original post. How do I determine if the key file is in decrypted format?

Created on Feb 27, 2012 1:23:12 PM



Download and extract the OpenSSL certificate utilities for Windows, for example, from: http://download.kerio.com/dwn/kms/sslcert.zip or from: http://www.slproweb.com/products/Win32OpenSSL.html

Then, use the tool to decrypt your key (please see the tool's help for details).

Created on Feb 28, 2012 4:38:07 PM by  Daniel Zobel [Product Manager]

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.