Write-Error: Cannot bind argument to parameter 'Exception' because it is null

I’ve run into a strange error using WinSCP's .NET Assembly to develop an SFTP client. It occurs when I call PutFileToDirectory() as follows:

try {
   $hostDirectory = Get-PathBelowWebRoot -root $pcRoot -file $file
   $remove = $false
   $session.PutFileToDirectory($file.fullName, $hostDirectory, $remove, $options)
}
catch {
   $errorObject = $Error[0]
   Write-Error $errorObject
   $($errorObject.InvocationInfo)
   exit
}

Upon calling PutFileToDirectory, execution goes to the catch block, and PowerShell issues this message:

> Write-Error: Cannot bind argument to parameter 'Exception' because it is null.

I've used $Error[0] successfully in the past to get error details, but for some reason it doesn’t work here.

Does anyone know how to discover the error details?

Output from $PSVersionTable.PSVersion:

Major  Minor  Patch  PreReleaseLabel BuildLabel
-----  -----  -----  --------------- ----------
7      3      4

I’m using the PowerShell extension to Visual Studio Code, version 1.79.0

This answer doesn't explain your symptom, but - based on your feedback - offers an effective workaround:

• There's no need to use the automatic $Error variable in your catch block - instead, use the automatic $_ variable to refer to the error at hand.

• If merely printing the error's message, i.e. its string representation is enough, you can use:

  Write-Error -Message $_
  

As an aside: if you're using exit in a script in response to an error, it's best to pass it a nonzero exit code to signal to the caller that an error occurred; e.g. exit 1.