Is it safe to presume the following statements are true?
* coxDS is the name of a volume
* coxDS belongs to the NetApp controller to which your script has most recently connected
* the user account under which the script is running (or the credentials provided to the Connect-NaController cmdlet) have sufficient rights on the NetApp
Are you able to run other commands successfully? For example:
$vols = Get-NaVol | Sort-Object -Property Name