While Microsoft's documentation states that asterisk wildcards (*) are supported in Windows Event Log queries, many developers encounter issues when implementing them in XPath filters. The official documentation suggests syntax like:

*[EventData[Data[@Name='TargetUserName'] ='User1*']]

This should theoretically match all events where TargetUserName starts with "User1", but in practice often returns no results.

When direct wildcard filtering fails, consider these approaches:

Method 1: Using contains() Function

*[EventData[Data[@Name='TargetUserName'] and contains(Data[@Name='TargetUserName'], 'User1')]]

Method 2: PowerShell Filtering Pipeline

Get-WinEvent -LogName Security | 
Where-Object {$_.Message -like "*User1*"} | 
Select-Object -First 100

Method 3: Custom XML Filter with starts-with()

<QueryList>
  <Query Id="0" Path="Security">
    <Select Path="Security">*[EventData[Data[@Name='TargetUserName'] 
    and starts-with(Data[@Name='TargetUserName'], 'User1')]]</Select>
  </Query>
</QueryList>

Wildcard operations can be resource-intensive on large logs. For production systems:

• Combine with time-based filters to limit scope
• Consider using wevtutil for bulk exports with subsequent filtering
• For frequent queries, create custom views in Event Viewer

For complex filtering needs that exceed XPath's capabilities, consider:

# PowerShell advanced filtering example
$filterHash = @{
    LogName = 'Security'
    ID = 4624 # Successful login
    StartTime = (Get-Date).AddDays(-1)
}
Get-WinEvent -FilterHashtable $filterHash | 
Where-Object { $_.Properties[5].Value -like "User1*" }

Remember that property indexes may vary by event ID, so verify positions with sample events first.

While Microsoft's documentation states that asterisk wildcards (*) are supported in XPath queries for Windows Event Log filtering, many developers encounter issues when trying to implement patterns like:

*[EventData[Data[@Name='TargetUserName'] ='User1*']]

Through testing various approaches, I've found that the contains() function provides more reliable wildcard-like behavior:

*[EventData[Data[@Name='TargetUserName'] and contains(., 'User1')]]

For more complex pattern matching, consider these approaches:

// Using starts-with() for prefix matching
*[EventData[Data[@Name='TargetUserName'] and starts-with(., 'User1')]]

// Using substring matching
*[EventData[Data[@Name='TargetUserName'] and substring(., 1, 5) = 'User1']]

Here's how to implement this in a PowerShell script:

Get-WinEvent -FilterHashtable @{
    LogName = 'Security'
    ID = 4624
} | Where-Object {
    $_.Properties[5].Value -like 'User1*'
}

• Wildcard behavior varies between Get-WinEvent and wevtutil
• Performance impact increases with complex queries
• Some event log providers may not fully support XPath 1.0