use Win32::OLE;

my $net=Win32::OLE->CreateObject("Wscript.Network");

$net->MapNetworkDrive("Y:","\\\\server\\path",0,"USERID","PASSWORD");

# deine Kopierroutine auf das Laufwerk Y:

# melde Laufwerk wieder ab
$net->RemoveNetworkDrive("Y:",1,0);
$net = '';