Ok I have worked it out, M$ are crap .

No really if I run a login script that maps some network printers and sets a network printer as defualt. Works Fine.

If I map some network printers and set a network printer as default then set local printer as default. Don't Work.

If I map network printers, sleep for 30 seconds and them map the local printers. It Works.

??? Sorry Users no Local Default Printers. .

Thanks