Update DNS Server setting on Multiple Servers with powershell

Had to update the DNS server settings on a few servers (80+).
Because I had a mix 23/28/28r2/12 servers decided wmi was the path forward + powershell.

issues with when doing contains, until I performed a convert to string [String]

Stumped by the String setting for a little while was trying .tostring()

Script in 3 parts:

1. check all the servers to see if hard code to old DC
2. Update the DHCP server options on all authorised DHCP servers
3. Purge any scope with setting for old DC to use the server option

Btw: some servers dont reply correctly to WMI so... prepared to check manually (and maybe fix wmi)

#StartHere :)
$OUName= 'OU=Servers,DC=KoolKids'
$TheComputers = Get-ADComputer -filter * -searchbase $OUName
$results = @()

Foreach ($server in $TheComputers) {
if(Test-Connection $server.name -Count 1 -quiet){
            $NICs = Get-WMIObject Win32_NetworkAdapterConfiguration -computername $server.name| where{$_.IPEnabled -eq “TRUE”} 
                Foreach($NIC in $NICs) {
                $FTW=$NIC.DNSServerSearchOrder
                $FTW =[String]$FTW
               # write-host $FTW
                If ($FTW.contains("10.10.3.1")) {
                                       $results += New-Object PSObject -Property @{
                                       Server = $server.name
                                       DNS = $FTW
                                          }
                            #update the DNS Server for this NIC
                            $DNSServers = "172.18.0.10","172.18.0.11"
                            $NIC.SetDNSServerSearchOrder($DNSServers)
                    }
                }
        }
    }
#set the default server scope options to correct setting
 foreach ($dhcpserver in Get-DhcpServerInDC){
 if(Test-Connection $dhcpserver.DNSName  -Count 1 -Quiet){
            #Remarked out so that all active DHCP servers get updated!
            #If ($FTW.contains("10.10.3.1")) { 
             $FixScope=[System.Net.Dns]::GetHostAddresses($dhcpserver.DNSName).IPAddressToString, "172.18.0.10", "172.18.0.11"
             Set-DhcpServerv4OptionValue -ComputerName $dhcpserver.DNSName -OptionId 6 -Value $FixScope
            #}
        }
 }

 #clear out the scope options
 # WARNING SERVER OPTIONS MUST HAVE a SETTING OR BAD THINGS HAPPEN
  foreach ($dhcpserver in Get-DhcpServerInDC){
             foreach ($TheScope in (Get-dhcpserverv4scope -computername $dhcpserver.DnsName)){
                     $target=$null
                     $Target=Get-DhcpServerv4OptionValue -ComputerName $dhcpserver.DNSName -OptionId 6 -ScopeId $TheScope.ScopeId -ErrorAction SilentlyContinue
                     $Target=[String]$target.Value
                      If ($Target.contains("10.10.3.1")) {
                      Remove-DhcpServerv4OptionValue -ComputerName $dhcpserver.DNSName -OptionId 6 -ScopeId $TheScope.ScopeId 
                      }
        }
 }