BSD-like (AKA “CopyCentre”) – here is the source, do as you please with it. (Earlier versions also required that you always acknowledge my authorship.)
Microsoft doesn't mind BSD-like CopyCentre licences as much as they hate the GPL, because they're allowed to include executable code without source, in their own products. Most of the original windows TCP/IP code and utilities was lifted from FreeBSD and (as required by the licence at the time) still contained the "Regents of the University of California" copyright notice.
One page links to CopyCentre:
