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icmp #1231 error



when I ping at command line, it works but in prtg, it shows the system is down 'icmp error #1231'.

It was working almost without any error.

what can be the problem?

error icmp prtg

Created on May 30, 2014 3:08:39 PM

2 Replies




thank you very much for your KB-Post. PRTG uses a standard Windows API Call to ping targets. So it just passes the target IP / Hostname to Windows, and Windows then in turn returns the ping response times, or errors. So here, Windows passes back the "ICMP #1231"-error.
It is an odd error though, please try if the suggestions from the folioing MSDN-Threads help:

best regards.

Created on Jun 3, 2014 8:29:43 AM by  Torsten Lindner [Paessler Support]



It is working now!

Somehow the gateway ip was disappeared (i don't know how). Anyway it works and I appreciate your support.


Created on Jun 3, 2014 6:03:05 PM

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