Querying Event Logs

I noticed that there is a huge speed difference between using an XML Query and PowerShell Get-EventLog piped through Where-Object to filter event logs. Thanks to this article, I learned how to use the XML Query via PowerShell, so you get the best of both worlds.

Know your version

Here's different commands that will show you which version PowerShell you're running.

$PSVersionTable.PSVersion

Get-Host

$host

$host.version

General concepts

There are two different cmdlets for accessing Windows Event Logs. Get-WinEvent is a newer version of Get-EventLog.

Get-WinEvent

You have access to more information
Because you have more information, it might take more effort to filter the data

Get-EventLog

One clear advantage: you can use the -After and -Before attributes to easily filter results by date

Filtering results

If you want to know how to filter the results, simply pipe the cmdlet to Get-Member:

Get-EventLog system -newest 1 | Get-Member

The output of the command clearly shows you the methods and properties returned:

PS C:\> Get-EventLog system -newest 1 | Get-Member


   TypeName: System.Diagnostics.EventLogEntry#system/nhi/1074012975

Name                      MemberType     Definition
----                      ----------     ----------
Disposed                  Event          System.EventHandler Disposed(System.Object, System.EventArgs)
CreateObjRef              Method         System.Runtime.Remoting.ObjRef CreateObjRef(type requestedType)
Dispose                   Method         void Dispose(), void IDisposable.Dispose()
Equals                    Method         bool Equals(System.Diagnostics.EventLogEntry otherEntry), bool Equals(System.Object obj)
GetHashCode               Method         int GetHashCode()
GetLifetimeService        Method         System.Object GetLifetimeService()
GetObjectData             Method         void ISerializable.GetObjectData(System.Runtime.Serialization.SerializationInfo info, System.Runtime.Serialization.StreamingContext context)
GetType                   Method         type GetType()
InitializeLifetimeService Method         System.Object InitializeLifetimeService()
ToString                  Method         string ToString()
Category                  Property       string Category {get;}
CategoryNumber            Property       int16 CategoryNumber {get;}
Container                 Property       System.ComponentModel.IContainer Container {get;}
Data                      Property       byte[] Data {get;}
EntryType                 Property       System.Diagnostics.EventLogEntryType EntryType {get;}
Index                     Property       int Index {get;}
InstanceId                Property       long InstanceId {get;}
MachineName               Property       string MachineName {get;}
Message                   Property       string Message {get;}
ReplacementStrings        Property       string[] ReplacementStrings {get;}
Site                      Property       System.ComponentModel.ISite Site {get;set;}
Source                    Property       string Source {get;}
TimeGenerated             Property       datetime TimeGenerated {get;}
TimeWritten               Property       datetime TimeWritten {get;}
UserName                  Property       string UserName {get;}
EventID                   ScriptProperty System.Object EventID {get=$this.get_EventID() -band 0xFFFF;}

Get-EventLog Examples

# Show available event logs and stats
Get-EventLog -List

# get the most recent 10 system log entries
# just change the LogName from System to Application, Security, etc. to access other logs
Get-EventLog -LogName System -Newest 10

# get all system logs from the last 4 hours
Get-EventLog -LogName System -After (Get-Date).AddHours(-4)

# get all system logs from the last 24 hours
Get-EventLog -LogName System -After (Get-Date).AddDays(-1)

# View specific event using the event Index
Get-EventLog -LogName System -Index [Event_Index_Number] | Format-List

# get the most recent 10 entries from a specific source
Get-EventLog -LogName System -Source Kerberos -Newest 10
Get-EventLog -LogName System -Source Microsoft-Windows-WLAN-AutoConfig -Newest 10

# Get system logs from the last 24 hours from Source WLAN-AutoConfig 
Get-EventLog -LogName system -After (Get-Date).AddDays(-1) -Source Microsoft-Windows-WLAN-AutoConfig

# get the most recent 10 Error entries
Get-EventLog -LogName Application -EventType Error -Newest 10
Get-EventLog -LogName Security -EventType Error -Newest 10
Get-EventLog -LogName System -EventType Error -Newest 10

# Get list of Event Log Sources from the System log from the last 8 hours sorted by log count
Get-EventLog -LogName System -after (Get-Date).AddHours(-8) | Group-Object -Property Source -NoElement | Select-Object -Property Count, Name | Sort-Object -Descending Count

# Find logins in the last 24 hours
Get-EventLog system -after (get-date).AddDays(-1) | where {$_.InstanceId -eq 7001}

# Find last computer start
$today = get-date -Hour 0 -Minute 0;
Get-EventLog system -after $today | sort -Descending | select -First 1

# Find logins and logoffs in the last 7 days
$logs = get-eventlog system -source Microsoft-Windows-Winlogon -After (Get-Date).AddDays(-7);
$res = @(); ForEach ($log in $logs) {if($log.instanceid -eq 7001) {$type = "Logon"} Elseif ($log.instanceid -eq 7002){$type="Logoff"} Else {Continue} $res += New-Object PSObject -Property @{Time = $log.TimeWritten; "Event" = $type; User = (New-Object System.Security.Principal.SecurityIdentifier $Log.ReplacementStrings[1]).Translate([System.Security.Principal.NTAccount])}};
$res

Get-WinEvent Examples

# Get user Logon / Logoff events
Get-WinEvent -FilterHashtable @{
   LogName='System'
   ProviderName='Microsoft-Windows-Winlogon'
   ID=7001,7002
}

Get-WinEvent -FilterHashtable @{
   LogName='Application'
   ProviderName='.NET Runtime'
   Keywords=36028797018963968
   ID=1023
   Level=2
}

Formatting output

Source

You can see what formatters are available on any system using the following command

Get-Command -Verb Format -Module Microsoft.PowerShell.Utility

Below is the output on Windows 11 as of 10/31/2023

PS C:\> Get-Command -Verb Format -Module Microsoft.PowerShell.Utility

CommandType     Name                                               Version    Source
-----------     ----                                               -------    ------
Function        Format-Hex                                         3.1.0.0    Microsoft.PowerShell.Utility
Cmdlet          Format-Custom                                      3.1.0.0    Microsoft.PowerShell.Utility
Cmdlet          Format-List                                        3.1.0.0    Microsoft.PowerShell.Utility
Cmdlet          Format-Table                                       3.1.0.0    Microsoft.PowerShell.Utility
Cmdlet          Format-Wide                                        3.1.0.0    Microsoft.PowerShell.Utility

You also have access to the following cmdlets for other output formats

Export-CliXml

# Export-Clixml exports an XML representation of an object or objects and stores it in a file
Get-Acl C:\Windows | Export-CliXml -Path .\c-windows-acl.xml

# You can use Import-CliXml to save the stored object or objects back to a variable
$WindowsFolderACL = Import-CliXml -Path .\c-windows-acl.xml

Export-Csv

# Export-Csv - Add an example later

Redirecting data with Out-* cmdlets

Source

Out-Host -Paging

Get-Process | Out-Host -Paging | Format-List

Get-Process | Format-List | Out-Host -Paging

Get-Command | Out-Null

Get-Command Get-Command | Out-Printer -Name 'Microsoft Office Document Image Writer'

Get-Process | Out-File -FilePath C:\temp\processlist.txt

Get-Command | Out-File -FilePath c:\temp\output.txt -Width 2147483647

Get-EventLog -LogName System -After (Get-Date).AddDays(-1) -EntryType Error | Out-GridView

Grouping output

Remember to use the Get-Member cmdlet to see what properties you can use with Sort-Object and -GroupBy

Get-Service -Name win* | Sort-Object StartType | Format-Table -GroupBy StartType -AutoSize

PS C:\> Get-Service -Name win* | Sort-Object StartType | Format-Table -GroupBy StartType -AutoSize


   StartType: Automatic

Status  Name      DisplayName
------  ----      -----------
Running Winmgmt   Windows Management Instrumentation
Running WinDefend Microsoft Defender Antivirus Service


   StartType: Manual

Status  Name                DisplayName
------  ----                -----------
Stopped WinRM               Windows Remote Management (WS-Management)
Running WinHttpAutoProxySvc WinHTTP Web Proxy Auto-Discovery Service

Querying for specific logs

System uptime related logs

For the actual current system uptime via PowerShell, look here.

Use this XML Filter in the Windows Event Viewer to create a custom filtered view of Kernel-General "The operating system started at system time..." events.

<QueryList>
  <Query Id="0" Path="System">
    <Select Path="System">*[System[(EventID='12')]]</Select>
    <Select Path="System">*[System[(EventID='13')]]</Select>
  </Query>
</QueryList>

Actual log message

Log Name:      System
Source:        Microsoft-Windows-Kernel-General
Date:          5/30/2023 7:48:33 PM
Event ID:      12
Task Category: (1)
Level:         Information
Keywords:      (128)
User:          SYSTEM
Computer:      [REDACTED]
Description:
The operating system started at system time ‎2023‎-‎05‎-‎31T02:48:32.500000000Z.
Event Xml:
<Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">
  <System>
    <Provider Name="Microsoft-Windows-Kernel-General" Guid="{a68ca8b7-004f-d7b6-a698-07e2de0f1f5d}" />
    <EventID>12</EventID>
    <Version>0</Version>
    <Level>4</Level>
    <Task>1</Task>
    <Opcode>0</Opcode>
    <Keywords>0x8000000000000080</Keywords>
    <TimeCreated SystemTime="2023-05-31T02:48:33.1346923Z" />
    <EventRecordID>74715</EventRecordID>
    <Correlation />
    <Execution ProcessID="4" ThreadID="8" />
    <Channel>System</Channel>
    <Computer>[REDACTED]</Computer>
    <Security UserID="S-1-5-18" />
  </System>
  <EventData>
    <Data Name="MajorVersion">10</Data>
    <Data Name="MinorVersion">0</Data>
    <Data Name="BuildVersion">19041</Data>
    <Data Name="QfeVersion">2075</Data>
    <Data Name="ServiceVersion">0</Data>
    <Data Name="BootMode">0</Data>
    <Data Name="StartTime">2023-05-31T02:48:32.5000000Z</Data>
  </EventData>
</Event>

Finding account lockouts.

XML Query

Use this XML Filter in the Windows Event Viewer to create a custom filtered view displaying account lockouts.

<QueryList>
  <Query Id="0" Path="Security">
    <Select Path="Security">
      *[
        System[(EventID='4740')]
      ] 
    </Select>
  </Query>
</QueryList>

PowerShell Script - Slow method

Get-EventLog -LogName Security | Where-Object {$_.EventID -eq 4740} |
   Select-Object -Property TimeGenerated, Source, EventID, InstanceId, Message

PowerShell Script - Fast method

$query = @"
<QueryList>
  <Query Id="0" Path="Security">
    <Select Path="Security">
      *[
        System[(EventID='4740')]
      ] 
    </Select>
  </Query>
</QueryList>
"@

Get-WinEvent -FilterXml $query | Format-List

Finding account lockouts for a particular user.

XML Query

Use this XML Filter in the Windows Event Viewer to create a custom filtered view displaying account lockouts for the administrator user.

<QueryList>
  <Query Id="0" Path="Security">
    <Select Path="Security">
      *[
        EventData[Data[@Name='TargetUserName']='administrator']
        and
        System[(EventID='4740')]
      ] 
    </Select>
  </Query>
</QueryList>

PowerShell Script - Fast method

$query = @"
<QueryList>
  <Query Id="0" Path="Security">
    <Select Path="Security">
      *[
        EventData[Data[@Name='TargetUserName']='administrator']
        and
        System[(EventID='4740')]
      ] 
    </Select>
  </Query>
</QueryList>
"@

Get-WinEvent -FilterXml $query | Format-List

NPS + Azure MFA Logs - XML Query

XML Filter for custom filtered view that suppresses accounting event logs.

<QueryXML>
	<QueryList>
	  <Query Id="0" Path="System">
		<Select Path="System">*[System[Provider[@Name='NPS']]]</Select>
		<Select Path="Security">*[System[Provider[@Name='Microsoft-Windows-Security-Auditing'] and Task = 12552]]</Select>
		<Suppress Path="Security">*[System[Provider[@Name='Microsoft-Windows-Security-Auditing'] and Task = 12552 and (Data='Network Policy Server discarded the accounting request for a user.')]]</Suppress>
		<Select Path="Security">*[System[Provider[@Name='Microsoft-Windows-Security-Auditing']]] and *[EventData[Data[@Name='LogonProcessName'] and (Data='IAS')]]</Select>
		<Select Path="AuthNOptCh">*</Select>
		<Select Path="AuthZAdminCh">*</Select>
		<Select Path="AuthZOptCh">*</Select>
	  </Query>
	</QueryList>
</QueryXML>

NPS Logs - XML Query

XML Filter for custom filtered view that suppresses accounting event logs.

<QueryXML>
	<QueryList>
	  <Query Id="0" Path="System">
		<Select Path="System">*[System[Provider[@Name='NPS']]]</Select>
		<Select Path="Security">*[System[Provider[@Name='Microsoft-Windows-Security-Auditing'] and Task = 12552]]</Select>
		<Suppress Path="Security">*[System[Provider[@Name='Microsoft-Windows-Security-Auditing'] and Task = 12552 and (Data='Network Policy Server discarded the accounting request for a user.')]]</Suppress>
		<Select Path="Security">*[System[Provider[@Name='Microsoft-Windows-Security-Auditing']]] and *[EventData[Data[@Name='LogonProcessName'] and (Data='IAS')]]</Select>
	  </Query>
	</QueryList>
</QueryXML>

Disk logs

XML Query

XML Filter for custom filtered view for disk events.

<QueryList>
  <Query Id="0" Path="System">
    <Select Path="System">*[System[Provider[@Name='disk']]]</Select>
  </Query>
</QueryList>

VPN Client Logs

PowerShell Query

$query = @"
<QueryList>
  <Query Id="0" Path="Application">
    <Select Path="Application">*[System[Provider[@Name='RasAuto' or @Name='RasCfg' or @Name='RasClient' or @Name='Rasman' or @Name='Microsoft-Windows-RasServer' or @Name='Microsoft-Windows-RasSstp' or @Name='Microsoft-Windows-EapMethods-RasChap' or @Name='Microsoft-Windows-NcdAutoSetup' or @Name='Microsoft-Windows-NCSI' or @Name='Microsoft-Windows-NetworkProfile']]]</Select>
    <Select Path="System">*[System[Provider[@Name='RasAuto' or @Name='RasCfg' or @Name='RasClient' or @Name='Rasman' or @Name='Microsoft-Windows-RasServer' or @Name='Microsoft-Windows-RasSstp' or @Name='Microsoft-Windows-EapMethods-RasChap' or @Name='Microsoft-Windows-NcdAutoSetup' or @Name='Microsoft-Windows-NCSI' or @Name='Microsoft-Windows-NetworkProfile']]]</Select>
  </Query>
</QueryList>
"@

$vpnEvents = Get-WinEvent -FilterXml $query -Oldest

# Displays events from the last 24 hours grouped by ProviderName
# This is the best view for easily browsing
$vpnEvents | ?{$_.TimeCreated -ge (Get-Date).Addhours(-24)}

# Displays events from the last 24 hours as a time sorted list
$vpnEvents | ?{$_.TimeCreated -ge (Get-Date).Addhours(-24)} | Format-List

XML Query

<QueryList>
  <Query Id="0" Path="Application">
    <Select Path="Application">*[System[Provider[@Name='RasAuto' or @Name='RasCfg' or @Name='RasClient' or @Name='Rasman' or @Name='Microsoft-Windows-RasServer' or @Name='Microsoft-Windows-RasSstp' or @Name='Microsoft-Windows-EapMethods-RasChap' or @Name='Microsoft-Windows-NcdAutoSetup' or @Name='Microsoft-Windows-NCSI' or @Name='Microsoft-Windows-NetworkProfile']]]</Select>
    <Select Path="System">*[System[Provider[@Name='RasAuto' or @Name='RasCfg' or @Name='RasClient' or @Name='Rasman' or @Name='Microsoft-Windows-RasServer' or @Name='Microsoft-Windows-RasSstp' or @Name='Microsoft-Windows-EapMethods-RasChap' or @Name='Microsoft-Windows-NcdAutoSetup' or @Name='Microsoft-Windows-NCSI' or @Name='Microsoft-Windows-NetworkProfile']]]</Select>
  </Query>
</QueryList>

Searching for Wired/WLAN-AutoConfig related errors

Original source

Wired-AutoConfig

#Powershell
$addhours = 12;

# Setup filter for error only logs
$filter = @{ LogName = "Microsoft-Windows-Wired-AutoConfig/Operational"
StartTime = [DateTime]::Now.AddHours($addhours*-1)
EndTime = [DateTime]::Now
Level = 2
}

Write-Host ([DateTime]::Now.AddHours($addhours*-1))

Write-Host ([DateTime]::Now)

$Events = Get-Winevent -FilterHashtable $filter



# Parse out the event message data            
ForEach ($Event in $Events) {            
	# Convert the event to XML            
	$eventXML = [xml]$Event.ToXml()            
	# Iterate through each one of the XML message properties            
	For ($i=0; $i -lt $eventXML.Event.EventData.Data.Count; $i++) {            
		# Append these as object properties            
		Add-Member -InputObject $Event -MemberType NoteProperty -Force -Name $eventXML.Event.EventData.Data[$i].name -Value $eventXML.Event.EventData.Data[$i].'#text'            
	}            
}

# Show results stored in variable
$Events | Format-List

WLAN-AutoConfig

#Powershell
$addhours = 12;

# Setup filter for error only logs
$filter = @{ LogName = "Microsoft-Windows-WLAN-AutoConfig/Operational"
StartTime = [DateTime]::Now.AddHours($addhours*-1)
EndTime = [DateTime]::Now
Level = 2
}

Write-Host ([DateTime]::Now.AddHours($addhours*-1))

Write-Host ([DateTime]::Now)

$Events = Get-Winevent -FilterHashtable $filter



# Parse out the event message data            
ForEach ($Event in $Events) {            
	# Convert the event to XML            
	$eventXML = [xml]$Event.ToXml()            
	# Iterate through each one of the XML message properties            
	For ($i=0; $i -lt $eventXML.Event.EventData.Data.Count; $i++) {            
		# Append these as object properties            
		Add-Member -InputObject $Event -MemberType NoteProperty -Force -Name $eventXML.Event.EventData.Data[$i].name -Value $eventXML.Event.EventData.Data[$i].'#text'            
	}            
}       

$Events | Select-Object id, MachineName, ProcessId,TimeCreated, Adapter, LocalMac, SSID, Cipher, Auth, PeerMac | Format-List

# Show results stored in variable
$Events | Select-Object id, MachineName, ProcessId,TimeCreated, Adapter, LocalMac, SSID, Cipher, Auth, PeerMac | Format-List

Show available wireless profiles and available wireless networks

# show profiles
netsh wlan show profiles

# show available networks
netsh wlan show networks

Duo Security Events

# Get Duo Security related events
Get-WinEvent -FilterHashtable @{
   LogName='Application'
   ProviderName='Duo Security'
}

Sources: 1

Basics

Errors and Solutions

Useful Commands

Querying Event Logs

Active Directory

Firewall management

Querying Event Logs

Know your version

General concepts

Get-WinEvent

Get-EventLog

Filtering results

Get-EventLog Examples

Get-WinEvent Examples

Formatting output

Export-CliXml

Export-Csv

Redirecting data with Out-* cmdlets

Grouping output

Querying for specific logs

System uptime related logs

Finding account lockouts.

XML Query

PowerShell Script - Slow method

PowerShell Script - Fast method

Finding account lockouts for a particular user.

XML Query

PowerShell Script - Fast method

NPS + Azure MFA Logs - XML Query

NPS Logs - XML Query

Disk logs

XML Query

VPN Client Logs

Searching for Wired/WLAN-AutoConfig related errors

Wired-AutoConfig

WLAN-AutoConfig

Show available wireless profiles and available wireless networks

Duo Security Events