winipcfg

[SPN]

Hi
situation:
users who log on on a domain at school using a 10/100 nic
at home they use their dail-in account
but often they can't get on to the network 'cause the nic still uses the ip
(laptop thinks ít's still connected via lan)

i've made a batch file
winipcfg /release_all
that bat file is executed when they dail-in
(properties of dail-in shortcut: scripting)
that worked but it also opens the winipcfg window and the users don't really understand that (basically they're flipping 'cause they 'think the computer is broken :) )
is their a way to do the same thing (winipcfg /release_all) without opening the window

thanks