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Windows update stopped the gui from running and app from connecting



After the recent updates for Windows, dated April 19, 2021 the next time I logged back in to the server the gui would not load at the previous ip.

Previous to the updates C:\Program Files (x86)\PRTG Network Monitor\PRTG GUI Starter.exe would load at (my chosen home page)

But now after the updates it loads on the private ip of the machine

It did only take a few minutes to realize this.

After I logged on one time on the private ip it now answers on either the private ip or the local host ip, but now running the gui forwards to the local ip instead of local host.

I am fine with either ip answering but I did find it strange that the latest update seemed to be what changed this behavior.

Worse then that is the fact that neither of my phones can now reach the server either. I have 2 android phones running the prtg app (2 different providers) and then now both fail to reach the server, and both were fine before the windows updates.

I double checked to make sure the core and probe services are running.

For some reason, after the windows updates I now had to change my app on both phones to 8443 instead of 443 as a temporary work around.

I saw this happened back in Nov 2019 and it was a change in NPCAP, maybe that was affected again.

Using various tools I determined that during a boot it seems that prtg was not binding to 443.

I found that after a reboot if I manually restarted the services, it would then bind properly to 443

So I set the prtg service (both core and probe) to automatic with delayed.

This seems to have taken care of it temporarily, although it does now take a little longer to be accessible by the apps from outside after reboots.

I am running PRTG on Windows Server 2016.

Should I try a reinstall or wait a day or so to see if you guys can recreate this?

app prtg update web-gui

Created on Apr 20, 2021 12:34:08 PM


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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.