Advanced Windows PowerShell Scripting Video Training

Advanced Windows PowerShell Scripting Video Training
Advanced Windows PowerShell Scripting Video Training

Friday, January 8, 2016

Reading and Resolving PowerShell Errors - Part 5

This is part 5 of my series of the most common PowerShell errors that are made in my PowerShell classes.  I will be posting one a day to help you understand why an error occurred and what the error’s meaning is.

Today’s error: The input object cannot be bound to any parameters for the command either because the command does not take pipeline input or the input and its properties do not match any of the parameters that take pipeline input.

Here is our starting code:
Get-ADComputer -filter * |
    Select-Object -Property @{Name="ComputerName";Expression={$_.Name}}|
        Get-WMIobject -ClassName Win32_Bios


And here is the full error:
Get-WMIobject : The input object cannot be bound to any parameters for the command either because the command does not take pipeline
input or the input and its properties do not match any of the parameters that take pipeline input.
At line:3 char:9
+         Get-WMIobject -ClassName Win32_Bios
+         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : InvalidArgument: (@{ComputerName=DomainAdmins1}:PSObject) [Get-WmiObject], ParameterBindingException
    + FullyQualifiedErrorId : InputObjectNotBound,Microsoft.PowerShell.Commands.GetWmiObjectCommand
 

We need to ask ourselves “What information am I passing to Get-WMIObject?” and “Why?”  If we execute the first two commands we get this:
ComputerName                                                                                                                            
------------                                                                                                                             
DC                                                                                                                                      
SVR1                                                                                                                                     
CL1                                                                                                                                     
SVR2                                                                                                                                     
EX1                                                                                                                                     
DomainAdmins1 

By the looks of things, we are passing objects with a ComputerName property to Get-WMIObject.  I’m willing to bet the intent is to execute Get-WMIObject against remote devices.  OK, is this possible through the PowerShell Pipeline.  Let’s see if Get-WMIObject has a –ComputerName parameter.
-ComputerName []
    Specifies the target computer for the management operation. Enter a fully qualified domain name, a NetBIOS name, or an IP
    address. When the remote computer is in a different domain than the local computer, the fully qualified domain name is
    required.
   
    The default is the local computer. To specify the local computer, such as in a list of computer names, use "localhost",
    the local computer name, or a dot (.).
   
    This parameter does not rely on Windows PowerShell remoting, which uses WS-Management. You can use the ComputerName
    parameter of Get-WmiObject even if your computer is not configured to run WS-Management remote commands.
   
    Required?                    false
    Position?                    named
    Default value                none
    Accept pipeline input?       false
    Accept wildcard characters?  false

It does, and it accepts multiple values.  The only problem, it does not accept input from the pipeline.  This will not work unless we recode.

Resolution:

Use ForeEach-Object.
ForeEach-Object has the unique capability of tricking cmdlets into being used in the PowerShell pipeline.  Take a look at this code:
Get-ADComputer -filter * |
    ForEach-Object {
        Get-WMIobject -ClassName Win32_Bios -ComputerName $_.Name
    }

Here we are encapsulating the Get-WMIObject cmdlet inside of ForEach-Object. We do need to explicitly use the –ComputerName parameter of Get-WMIObject. Remember, it does not accept pipeline input and we are not attempting to pass it pipeline input directly.  We also need to specify which property of the current object in the PowerShell Pipeline that we want to use.  In this case, it is the value of the name property.



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