[maxmsp] send object crashes app

Hello
Started to work with MAX 5.0. Looks very exciting...
something strange with SEND object. Double clicking it shuts the application. By the way, similar thing happens when trying to get help for EXPR object. Right ckick crashes MAX instead of showing help.
any advise about it?

thanks
Alex

MAX 5.0
VISTA HOME PREMIUM
OS VERSION 6.0.6000
INTEL(r) CORE(tm)2 DUO CPU T9300 @ 2.5 GHz 2493 MHz

Realtek High Definition Audio
NVIDIA GeForce 8600M GT
installed drivers: nvd3dum.dll,nvwgf2um.dll
driver version: 7.15.11.5655