How can I rethrow an exception from catch block in PowerShell?
If you would like to re-throw original exception you could use throw (most common), or throw $_, or throw $_.Exception
ps: inside catch variable $_ is not exception by itself, but System.Management.Automation.ErrorRecord that contains Exception
Note
The throw keyword at PowerShell behaves differently then .NET implementation: in .NET you can only throw System.Exceptions itself or its successors, but in PowerShell, you can throw anything and that is automatically wrapped up into a System.Management.Automation.RuntimeException. See snippet here.