I need to be able to download and install a new versions of my program when
user login to my server. This will be very simular to the windows update
routine.

Got most of it figured out except for:

a) Anyway other than using a master launching type program to replace the
very program that performs the connection?

b) This connection program may be run by a user with limited rights on the
machine. How can I bypass this and install my new copy of the program?