PowerShell Error Catching

PowerShell error catching has been very frustrating for me. I try to do the right thing by putting code in a Try-Catch-Finally block, but continue to struggle with catching specific errors. I don’t know why the ‘thing’ I need to catch is not output with the error. I have to go through the error and ‘hunt’ for the thing to catch. Below is the basic syntax for a PowerShell Try-Catch-Finally block.

try {
    # Do something
} catch [something here to catch] {
    # Handle the error
} finally {
    # This section will always run
}

The sample below is similar to what you would typically see after an error is caught. Unfortunately, there is nothing in the output that you can use to ‘catch’.

$Error[0] | Format-List * -Force

This will show a longer output of the error, and more specifically, the ‘thing’ to ‘catch’. See the highlighted text below.

Now that there is a specific Exception to catch, we can add a new catch block to our Try-Catch-Finally block.

try {
    # Do something
} catch [System.Management.Automation.ParameterBindingException] {
    # Handle the specific error
} finally {
    # This section will always run
}

The best help I was able to find for this came from a Spiceworks post by Duffney, https://community.spiceworks.com/how_to/121063-using-try-catch-powershell-error-handling. It was by far the easiest method to discover the specific error to use in the catch block.

I am not quite sure why it is so hard to find the exception to use in the catch block or why it is just not part of the error output. I suppose for someone who codes in PowerShell everyday, this post will be laughable. I just wanted to make sure I recorded a post for future reference because I know for sure, I will struggle with this concept again.