Unable to get PowerShell code to work

Question

I am trying to run a script from my Active Directory host to the other hosts on the network that will pull device info for each of the hosts.

The code I am using is:

# Exports Local System Information to CSV
# Run this PowerShelll script at log on to collect PC information to a CSV file on a network share
# Thom McKiernan 28/08/2014

#Get hostnames
#$Computers = Get-Content ("C:\Users\Administrator.ESP\Documents\SoftwareAuditing\ComputerDetails\ComputerListAug2015.txt") -ErrorAction SilentlyContinue

foreach ($computer in Get-Content "C:\Users\Administrator.ESP\Documents\SoftwareAuditing\ComputerDetails\ComputerListAug2015.txt")
{

# Collect the info from WMI
$computerSystem = get-wmiobject Win32_ComputerSystem -Computer $computer.$deviceinfile
$computerBIOS = get-wmiobject Win32_BIOS -Computer $computer.$deviceinfile
$computerOS = get-wmiobject Win32_OperatingSystem -Computer $computer.$deviceinfile
$computerCPU = get-wmiobject Win32_Processor -Computer $computer.$deviceinfile
$computerHDD = Get-WmiObject Win32_LogicalDisk -ComputerName $computer.$deviceinfile -Filter drivetype=3
$macAddress = Get-WmiObject win32_networkadapterconfiguration -Computer $computer.$deviceinfile -Filter "IpEnabled = TRUE"

#Build the CSV file
$csvObject = New-Object PSObject -property @{
    "PCName" = $computerSystem.Name
    "Manufacturer" = $computerSystem.Manufacturer
    "Model" = $computerSystem.Model
    "SerialNumber" = $computerBIOS.SerialNumber
    "RAM" = "{0:N2}" -f ($computerSystem.TotalPhysicalMemory/1GB) + "GB"
    "HDDSize" = "{0:N2}" -f ($computerHDD.Size/1GB) + "GB"
    "HDDFree" = "{0:P2}" -f ($computerHDD.FreeSpace/$computerHDD.Size) + "GB"
    "CPU" = $computerCPU.Name
    "OS" = $computerOS.caption
    "SP" = $computerOS.ServicePackMajorVersion
    "User" = $computerSystem.UserName
    "BootTime" = $computerOS.ConvertToDateTime($computerOS.LastBootUpTime)
    "MACAddress" = $macAddress.MacAddress
    } 

#Export the fields you want from above in the specified order
$csvObject | Select PCName, Maufacturer, Model, SerialNumber, RAM, HDDSize, HDDFree, CPU, OS, SP, User, BootTime, MACAddress | Export-Csv 'system-info.csv' -NoTypeInformation -Append

}

# Open CSV file for review (leave this line out when deploying)
notepad system-info.csv

However, I am continuously getting the following error:

Get-WmiObject : Cannot validate argument on parameter 'ComputerName'. The argument is null or empty. Supply an argument that is not null or empty and then try the command again.

I have tried to set up the txt file as just computer names (exported from Active Directory) and I have tried to append each name with ".domain.com" and neither have worked.

I tried to have just my own device in the list, and no error occurred, but there was no output either. It was as if it didn't run when using "powershell -noexit .\ComputerDetails.ps1" but when I just run the script by right-clicking on it I can see the errors fly by, and an error from Notepad saying the file does not exist.

I have tried to google this issue, and found countless resources, that do not seem to help get rid of this error.

Full list of errors recieved:

Get-WmiObject : Cannot validate argument on parameter 'ComputerName'. The argum
ent is null or empty. Supply an argument that is not null or empty and then try
 the command again.
At C:\Users\Administrator.ESP\Documents\SoftwareAuditing\ComputerDetails\Comput
erDetails.ps1:12 char:63
+ $computerSystem = get-wmiobject Win32_ComputerSystem -Computer <<<<  $compute
r.$deviceinfile
    + CategoryInfo          : InvalidData: (:) [Get-WmiObject], ParameterBindi
   ngValidationException
    + FullyQualifiedErrorId : ParameterArgumentValidationError,Microsoft.Power
   Shell.Commands.GetWmiObjectCommand

Get-WmiObject : Cannot validate argument on parameter 'ComputerName'. The argum
ent is null or empty. Supply an argument that is not null or empty and then try
 the command again.
At C:\Users\Administrator.ESP\Documents\SoftwareAuditing\ComputerDetails\Comput
erDetails.ps1:13 char:51
+ $computerBIOS = get-wmiobject Win32_BIOS -Computer <<<<  $computer.$deviceinf
ile
    + CategoryInfo          : InvalidData: (:) [Get-WmiObject], ParameterBindi
   ngValidationException
    + FullyQualifiedErrorId : ParameterArgumentValidationError,Microsoft.Power
   Shell.Commands.GetWmiObjectCommand

Get-WmiObject : Cannot validate argument on parameter 'ComputerName'. The argum
ent is null or empty. Supply an argument that is not null or empty and then try
 the command again.
At C:\Users\Administrator.ESP\Documents\SoftwareAuditing\ComputerDetails\Comput
erDetails.ps1:14 char:60
+ $computerOS = get-wmiobject Win32_OperatingSystem -Computer <<<<  $computer.$
deviceinfile
    + CategoryInfo          : InvalidData: (:) [Get-WmiObject], ParameterBindi
   ngValidationException
    + FullyQualifiedErrorId : ParameterArgumentValidationError,Microsoft.Power
   Shell.Commands.GetWmiObjectCommand

Get-WmiObject : Cannot validate argument on parameter 'ComputerName'. The argum
ent is null or empty. Supply an argument that is not null or empty and then try
 the command again.
At C:\Users\Administrator.ESP\Documents\SoftwareAuditing\ComputerDetails\Comput
erDetails.ps1:15 char:55
+ $computerCPU = get-wmiobject Win32_Processor -Computer <<<<  $computer.$devic
einfile
    + CategoryInfo          : InvalidData: (:) [Get-WmiObject], ParameterBindi
   ngValidationException
    + FullyQualifiedErrorId : ParameterArgumentValidationError,Microsoft.Power
   Shell.Commands.GetWmiObjectCommand

Get-WmiObject : Cannot validate argument on parameter 'ComputerName'. The argum
ent is null or empty. Supply an argument that is not null or empty and then try
 the command again.
At C:\Users\Administrator.ESP\Documents\SoftwareAuditing\ComputerDetails\Comput
erDetails.ps1:16 char:61
+ $computerHDD = Get-WmiObject Win32_LogicalDisk -ComputerName <<<<  $computer.
$deviceinfile -Filter drivetype=3
    + CategoryInfo          : InvalidData: (:) [Get-WmiObject], ParameterBindi
   ngValidationException
    + FullyQualifiedErrorId : ParameterArgumentValidationError,Microsoft.Power
   Shell.Commands.GetWmiObjectCommand

Get-WmiObject : Cannot validate argument on parameter 'ComputerName'. The argum
ent is null or empty. Supply an argument that is not null or empty and then try
 the command again.
At C:\Users\Administrator.ESP\Documents\SoftwareAuditing\ComputerDetails\Comput
erDetails.ps1:17 char:72
+ $macAddress = Get-WmiObject win32_networkadapterconfiguration -Computer <<<<
 $computer.$deviceinfile -Filter "IpEnabled = TRUE"
    + CategoryInfo          : InvalidData: (:) [Get-WmiObject], ParameterBindi
   ngValidationException
    + FullyQualifiedErrorId : ParameterArgumentValidationError,Microsoft.Power
   Shell.Commands.GetWmiObjectCommand

Attempted to divide by zero.
At C:\Users\Administrator.ESP\Documents\SoftwareAuditing\ComputerDetails\Comput
erDetails.ps1:27 char:53
+     "HDDFree" = "{0:P2}" -f ($computerHDD.FreeSpace/ <<<< $computerHDD.Size)
+ "GB"
    + CategoryInfo          : NotSpecified: (:) [], RuntimeException
    + FullyQualifiedErrorId : RuntimeException

Export-Csv : A parameter cannot be found that matches parameter name 'Append'.
At C:\Users\Administrator.ESP\Documents\SoftwareAuditing\ComputerDetails\Comput
erDetails.ps1:37 char:183
+ $csvObject | Select PCName, Maufacturer, Model, SerialNumber, RAM, HDDSize, H
DDFree, CPU, OS, SP, User, BootTime, MACAddress | Export-Csv 'system-info.csv'
-NoTypeInformation -Append <<<<
    + CategoryInfo          : InvalidArgument: (:) [Export-Csv], ParameterBind
   ingException
    + FullyQualifiedErrorId : NamedParameterNotFound,Microsoft.PowerShell.Comm
   ands.ExportCsvCommand

Solution

The issue you are having here is that PowerShell is trying to get the property defined by $deviceinfile from the object $computer. However $computer is just a string that does not have a property $deviceinfile. Is that supposed to be a suffix as part of your naming convention?

Brief Explanation of the issue

Look at the following example

$Computer = "comp1"
$deviceinfile = "Test"

$Computer.$deviceinfile

That returned nothing since there is not "Test" property on the $computer string object. I think the result you were expecting was comp1.Test. Now look at this example.

$deviceinfile = "Test"
$computer = New-Object -TypeName PSCustomObject -Property  @{Test = "Bagel"}
$Computer.$deviceinfile

We made an object with a property called Test. "Bagel" is what is returned from that code.

What you can do in your code

If this is a naming convention you need to put that into quotes to stop it from being treated like a property call. Those variable will be expanded the way you would expect them. That is of course assuming you have $deviceinfile defined before it is called.

$computerSystem = get-wmiobject Win32_ComputerSystem -Computer "$computer.$deviceinfile"

Else just remove it.

$computerSystem = get-wmiobject Win32_ComputerSystem -Computer $computer