Break On
Dim $BaseKey, $Key, $Value, $RC
$BaseKey = 'HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\Interfaces'
For each $Key in ArrayEnumKey($BaseKey)
  If AScan(ArrayEnumValue($BaseKey+'\'+$Key),'MTU')<>-1
   'Value ['+ReadValue($BaseKey+'\'+$Key,'MTU')+'] in Key ['+$Key+']' ?
;   $RC = WriteValue($BaseKey+'\'+$Key,'MTU','1400','REG_DWORD')
  EndIf
Next
  

Break On
Dim $BaseKey, $Key, $RC, $MTUvalue

; Edit MTU value below.

$MTUvalue = '1400'
$BaseKey = 'HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\Interfaces'


For each $Key in ArrayEnumKey($BaseKey)
$RC = WriteValue($BaseKey+'\'+$Key,'MTU', $MTUvalue ,'REG_DWORD')
Next



;UDF Functions Do Not Edit!
;UDF Function ArrayEnumKey

function arrayenumkey($regsubkey)
    dim $retcode, $subkeycounter, $currentsubkey, $subkeyarray
    
    if not keyexist($regsubkey)
        $arrayenumkey=''
        return
    endif
    
    $subkeycounter=0
    do
        $currentsubkey=enumkey($regsubkey,$subkeycounter)
        if $currentsubkey<>259 and @ERROR=0
            redim preserve $subkeyarray[$subkeycounter]
            $subkeyarray[$subkeycounter]=$currentsubkey
            $subkeycounter=$subkeycounter+1
        endif
    until $currentsubkey=259 or @ERROR
    
    $arrayenumkey=$subkeyarray
endfunction

;End UDF Functions.