opening files on client

["syed mehdi" <smmehadi@xxxxxxxxx>]

Hi,
I have placed a *.abc file at apache server document root (/var/www/html), this application opens with some registered application (say x) on client side.
Now whenver i try to open this file from client side (using some url like: http://machine-ip/*.abc), then it opens in binary mode, 
rather then opening with x application.
or say if i want to execute some exe like *.exe instead of *.abc on server side, then where should i place that on server and what changes should i make.
any help will be appreciated.

Thanks & Regards
Syed