Thanks for your reply - derby... On Win32 - Ping.exe gives Read/Execute and Read permissions to group Users, which is the same permission that myPing script fails under. I can ping.exe even as Guest. I already know that if I change the script to run as someone with admin rights that that will work. I was hoping to get the EACCES error so that I could confirm that NiX is not allowing me to write (send) to to ICMPECHO port... I can bind to an arbitrary socket. I tested that with another client/server with permissions User.