Because you didn't run the correct one. Check your path. on Wed, May 30, 2001 at 07:51:18PM -0700, Michael Gao wrote: > I just download a ns2.1b7a allinone packet and > installed it. But after that when i keyed "ns-version" > I found it is ns2.1b5. Why is that instead of > ns2.1b7a?