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Filtering out unwanted events from WMI Event Log




I would like to set up sensors for various Event IDs in the System log. The problem is that Windows is using the same IDs for different messages.

How can I exactly filter out events with a specific string in them?

I noticed there is a hint in the sensor settings (Filter by Message > Exclude Filter > Match String (Event Message) that a % character should be used in this case.

Can you provide some examples of how to use this? In my case, I need to discard all Events with the following text in them: "Login failed for user".

Thank you

eventlog windows wmi

Created on Feb 28, 2023 3:45:16 PM

5 Replies



Hello KrystianWy,

Thank you for the post, which sensor type are you working with?


What PRTG version do you have?

Regards, Oscar

Created on Mar 3, 2023 11:15:09 PM by  Oscar Chavarria [Paessler Technical Support]



Hi there!

Sensor Type: WMI Event Log, my PRTG version is


Created on Mar 8, 2023 9:52:46 AM



Can you try this settings?

Turn On:

Filter by User

Filter Type

Exclude filter:

Match String (Event User)

"Login failed for user"

Created on Mar 10, 2023 8:23:27 PM by  Oscar Chavarria [Paessler Technical Support]



Hi, I have tried using quotes and it didn't work, but encapsulating the string between two % signs did the trick (%Login failed for user%)

Hint from PRTG itself: "Enter the string that the sensor uses to filter for specific event messages. The sensor checks if this string is part of the message. You must use the percent sign % as wildcard if you want to check if the string is part of the message. Otherwise, the whole event message must match the string. Find more help in the PRTG Manual" Cheers

Created on Mar 13, 2023 3:11:47 PM



Thanks for coming back with the answer.


Created on Mar 15, 2023 11:18:50 PM by  Oscar Chavarria [Paessler Technical Support]

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