detect client side software version

I have web application, through I need it to read an application version on the client side.

is this possible? Can I do this in javascript, or even asp.net?

I want to determine the version of software installed on the client side.

For example:

The version of software that is installed, for instance if a user installs a program with name test.exe , I want to detect it and get its version. It's not browser plugin.

You need to use activeX to create object of any exposed type using JS. If it fails software is not installed, else u can retrieve version stored in activeX object. Thats how most messenger do.

<OBJECT id="MSXML4"
classid="clsid:88d969c0-f192-11d4-a65f-0040963251e5"
codebase="http://www..../msxml4.cab#version=4,10,9404,0"
type="application/x-oleobject"
STYLE="display: none"
standby="ww">
Alternative Text
</OBJECT>

<script>
//if msxml4 is not installed
if( !document.MSXML4 ){
alert("MSXML4 is not installed");
</script>
}