Make a batchfile with the necessary commands. That's IPCONFIG with the right parameters, followed by a RUNDLL32 for a programmatic shutdown. Then add a shortcut to that batchfile somewhere (Start>Programs, Desktop, Quick Launch, whatever you prefer) and use that.
It won't work for a shutdown via ALT-F4 or when done by Windows itself, for example if you answer "restart now" to a Windows update prompt. It won't even work with Start>Shutdown.
So some user discipline is necessary.
I was wondering if there was a script out there where I can automate the ipconfig /flushdns and then /release the IP commands when I shutdown my system.
Anybody know where to look? Thanks.