Need help with error handling; Get-WmiObject: Access is denied

I am new to powershell....like a week into it.

I have been asked to query all servers for IP info. Found a great script (Get-IPDetails.ps1) written by Sitaram Pamarthi 

My company has servers all over the world in 8 domains. When I run this command:
get-content "C:\scripts\CAP servers.txt" | .\Get-IPDetails.ps1 | export-csv C:\scripts\output.csv

I get the error Get-WmiObject: Access is denied on many of the servers

On the output.csv file each of those entries will have the ip details for the last successful entry

Example: (When running the command I saw Server2 received "Access Denied" during the process)
ComputerName     IPAddress
Server1                  10.10.10.10 (ping verified correct)
Server2                  10.10.10.10 (ping verified incorrect)
Server3                  10.128.20.5 (ping verified correct)

How do I tell the script not to output data for any server returning the "Access is denied" error?

Thanks.

[cmdletbinding()]

param (

 [parameter(ValueFromPipeline=$true,ValueFromPipelineByPropertyName=$true)]

    [string[]]$ComputerName = $env:computername

)            

begin {}

process {

 foreach ($Computer in $ComputerName) {

  if(Test-Connection -ComputerName $Computer -Count 1 -ea 0) {

   $Networks = Get-WmiObject Win32_NetworkAdapterConfiguration -ComputerName $Computer | ? {$_.IPEnabled}

   foreach ($Network in $Networks) {

    $IPAddress  = $Network.IpAddress[0]

    $SubnetMask  = $Network.IPSubnet[0]

    $DefaultGateway = $Network.DefaultIPGateway

    $DNSServers  = $Network.DNSServerSearchOrder

    $IsDHCPEnabled = $false

    If($network.DHCPEnabled) {

     $IsDHCPEnabled = $true

    }

    $MACAddress  = $Network.MACAddress

    $OutputObj  = New-Object -Type PSObject

    $OutputObj | Add-Member -MemberType NoteProperty -Name ComputerName -Value $Computer.ToUpper()

    $OutputObj | Add-Member -MemberType NoteProperty -Name IPAddress -Value $IPAddress

    $OutputObj | Add-Member -MemberType NoteProperty -Name SubnetMask -Value $SubnetMask

$OutputObj | Add-Member -MemberType NoteProperty -Name Gateway -Value ($DefaultGateway -join “,”)

    $OutputObj | Add-Member -MemberType NoteProperty -Name IsDHCPEnabled -Value $IsDHCPEnabled

    $OutputObj | Add-Member -MemberType NoteProperty -Name DNSServers -Value $DNSServers

    $OutputObj | Add-Member -MemberType NoteProperty -Name MACAddress -Value $MACAddress

    $OutputObj

   }

  }

 }

}            

end {}