thanks peter for your reply
again i didn't understand the meaning of "c:\temp\setup.iss" in the command line. Doesn't it tells the "avsetup" to get the required information for installing the software. Every time this program reaches the client end, and the program uses the mentioned command line, then for silent installation setup.iss file must be present or accessible . If "c:\temp\setup.iss" tells the location of the setup.iss from where the program will fetch the detail, should I not change this location to another location which would be accessible globally by all the users, it then can be accessed by all the clients from a same location while installing the software.
When this program will be distributed to the users, I don't want any input to be given by user.