PowerShell: Install and Uninstall App on Remote Machines

# Trigger uninstall of an MSI file
$computername="SERVER007"
$keywordSearch="Polycom*"
$installFile="\\FILESHERVER\Software\Polycom\Polycom_BToE_Connector_4.0.0.0 (new for 2019-07-19)\Polycom_BToE_Connector_4.0.0.0.msi"

# Trigger silent install of an MSI file
function installApp($installFile){
	msiexec.exe /i $installFile /qn /norestart
	"Install has been triggered. Waiting 30 seconds for app listing..."
	Sleep 30;
	get-wmiobject Win32_Product | Select IdentifyingNumber, Name
}

# Trigger silent uninstall of an MSI file
function uninstallApp ($appNameKeyword){
	#$productGUID=(get-wmiobject Win32_Product -ComputerName $computerTarget | Where-Object {$_.Name -like $appNameKeyword}).IdentifyingNumber;
	$productGUID=(get-wmiobject Win32_Product | Where-Object {$_.Name -like $appNameKeyword}).IdentifyingNumber;
	if ($productID){
		msiexec.exe /x $productGUID /qn;
		}
		else{
			"Application with keyword $appNameKeyword not found."
			# Check for exising installs
			#get-wmiobject Win32_Product -ComputerName $computername | Select IdentifyingNumber, Name
			get-wmiobject Win32_Product | Select IdentifyingNumber, Name
		}    
}

function installOnRemote($server,$app){  
  Invoke-Command -computername $server -credential $cred -ScriptBlock { 
      param( $x, $importedFunc)
      "Executing script on $($ENV:computername)..."
      # Import the function from the variable inside parameters
      [ScriptBlock]::Create($importedFunc).Invoke($x)
  } -ArgumentList $app, ${function:installApp}
}

function uninstallOnRemote($server,$app){  
  Invoke-Command -computername $server -credential $cred -ScriptBlock { 
      param( $x, $importedFunc)
      "Executing script on $($ENV:computername)..."
      # Import the function from the variable inside parameters
      [ScriptBlock]::Create($importedFunc).Invoke($x)
  } -ArgumentList $app, ${function:uninstallApp}
}



# Check whether a given username matches the list of Domain Admins
function validateDomainAdmin{
    param (
        [string]$username
    )
    $matchedAdmin=$username -in $domainAdmins
    if($matchedAdmin){
        Write-Host "$username is a Domain Admin";
        return $True;
        }else{
       Write-Host "$username not a Domain Admin.";
       return $False;
       }
}

function testCredential{
  param (
      [string]$username,
      [string]$password
  )
  $plaintextPassword = (New-Object System.Management.Automation.PSCredential 'N/A',$providedPassword).GetNetworkCredential().Password
  $domainBindTest = (New-Object System.DirectoryServices.DirectoryEntry($domainObject,$username,$plaintextPassword)).DistinguishedName
  if ($domainBindTest){return $True;} else{Return $False;}
}

function obtainDomainAdminCred{
	$domainAdmins=(Get-ADGroupMember -Identity "Domain Admins" -Recursive | %{Get-ADUser -Identity $_.distinguishedName} | Where-Object {$_.Enabled -eq $True}).SamAccountName
  $global:cred=$False
  do {
    $providedID=Read-Host -Prompt 'Input a domain admin username'
    if (validateDomainAdmin $providedID){
      $providedPassword = Read-Host -assecurestring "Please enter the password"
      #$providedPassword = [System.Runtime.InteropServices.Marshal]::PtrToStringAuto([System.Runtime.InteropServices.Marshal]::SecureStringToBSTR($password))
      #$providedCredential = New-Object -TypeName System.Management.Automation.PSCredential -ArgumentList $providedID,$providedPassword
      $goodCredential=testCredential -username $providedID -password $providedPassword
      if($goodCredential){
        "Domain Admin Credential validated!";
        $global:cred=New-Object -TypeName System.Management.Automation.PSCredential -ArgumentList $providedID,$providedPassword;
         #return $True;
         }
         else{   
         "Password doesn't match.";
         $global:cred=$False;
         #return $False;
         }
    }else{
    "Try again..."
    #return $False;
    }
  } until ($cred) 
}

obtainDomainAdminCred;
installOnRemote $computername $installFile;
uninstallOnRemote $computername $keywordSearch;