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Dcom issue unable to communicate with the a few computers a few times a day.



We are seeing issues during the day where around our PRTG sensor will have a brief inability to communicate with around 5 servers. They are all on the same LAN as the server running PRTG. In the windows event viewer I am seeing these errors that coincide with the issue DCOM was unable to communicate with the computer using any of the configured protocols; requested by PID 1688 (C:\Program Files (x86)\PRTG Network Monitor\PRTG Probe.exe), while activating CLSID

There will sometimes be this error roughly 10-20 minutes before this occurs 1 remote calls to the SAM database have been denied in the past 900 seconds throttling window.

The primary dns server for this server before was across the wan. I did just make a change to use a dns server on the same lan as the PRTG server and those that it is sometimes having issues with. I will reboot the PRTG server and see if changing the DNS server fixes the issue.

dcom prtg sensor

Created on Mar 31, 2022 11:15:16 PM

1 Reply



Hi Paul,

Thanks for your KB Post. Do you notice any Windows updates in both PRTG and the target servers? We have some past cases where some Windows Updates are the root cause of the issue.


With kind regards,
Chan Siau Hen
Technical Support Team, Paessler AG

Created on Apr 8, 2022 7:49:47 AM by  Chan Siau Hen [Paessler Technical Support]

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