is it .net version 2002, 2003 or 2005/express?
if its 05/express then you can change it in "application settings"
to get to application setitngs:
on the right (maybe somewhere else if you have moved it) there should be the "solution explorer" with form1, form2 etc and all your other project files.
Double click on the thing that reads "My project" (blue / gray folder icon) and a menu opens up where you can configure all the things like company name, optimisations ,and of course, icon file.
Once opened ity should look like this:
In Solution Explorer Right Click on Properties.
In Left side tab, Click On Common Properties -->> Build -->>
Right side u get Application Icon,
Browse and select required icon.
No problem. The best thank you is adding to my rep!