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Version update auto-applied overnight, now core service on server won't start?




I've had PRTG installed and running well on a win 2008 r2 server (I'll call it
officeserver here) at my office since late-June 2017. I've always let the service auto-upgrade and reboot that server in the evening whenever a upgrade was pushed out.

Until today I've never had a problem with PRTG restarting automatically after an upgrade. However today when I came into work I found that the web portal from another pc on my LAN (https://officeserver:8443/index.htm) could not reach the PRTG service on
officeserver when normally I can get to the PRTG login screen.

I remotely accessed
officeserver's desktop, hovered over the PRTG icon in the task bar, and found that the error displays of Not Connected (connection refused). I then open the Enterprise Console, it says 0 Alarms and Warnings at the top of the window, but the service entry says

Active127.0.0.1(my PRTG username)Status:Not Connected (Error in content: )

I try to edit the PRTG Server connection and notice the Port: is set at 80 instead of 8443 and Use SSL is not checked I tried changing the port to 8443 and checking the SSL box then selecting OK the connection seems to try to start, then goes back to the error of

Active127.0.0.1(my PRTG username)Status:Not Connected (Error in content: )

How do I get the server connection working again?

thanks, david

core-server port prtg ssl start-failure

Created on Jul 25, 2018 2:33:36 PM

Last change on Jul 26, 2018 5:22:00 AM by  Luciano Lingnau [Paessler]

2 Replies

Accepted Answer



Hello there and thank you for your inquiry.

I encourage you to leave the Enterprise Console application out of this for now, since it just adds one more variable to the problem.

The first thing to check, is whenever the PRTG Core Server Service (responsible for the web-interface) is present and running. If it isn't (listed or running), that is the most likely explanation for the issue.

If this is the case, I encourage you to begin by re-installing PRTG manually, to make sure that all webserver files are up-to-date and installed correctly. Please perform the following:

  1. Stop any running PRTG services using services.msc
  2. Download and install the most recent stable release.

Please do not attempt to install/update using this installer if you don't have active software maintenance. You can install it directly over the currently running version. The configuration and monitoring database won't be affected by installing the newest version over the old and the configuration is automatically backed up before this process. Please note that monitoring will be disrupted for a few minutes during the update, remote probes (if any) will automatically be updated after the core server is updated.

Please let us know how the system behaves after this. If you encounter issues starting either of PRTG's services, please share a screenshot of the error you get within the "PRTG Administration Tool" when you attempt to start the service.

After the web-interface is accessible getting the Enteprise Console connect (if relevant) should be relatively straightforward.

Best Regards,
Luciano Lingnau [Paessler Support]

Created on Jul 26, 2018 5:25:09 AM by  Luciano Lingnau [Paessler]

Last change on Jul 26, 2018 5:25:30 AM by  Luciano Lingnau [Paessler]



Thank you Luciano for your detailed help. I found that Prtg core server service was not running and you couldn't start it you'd get an error message of "file not found" I downloaded the trial version of prtg (that's what we use) and ran the setup exe. once the setup completed prtg was working normally again! thanks, david

Created on Jul 27, 2018 2:57:45 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.