Strange Error [Need Help FAST]
I'm using windows 8.1 Preview
.Net Framework installed
in any Vb.net app, When I Make any "Process.start" code this Comes out :

I Don't know what to do !! (I've never used windows8)
Sounds like Windows(R) doesn't know which program to open web-addresses with.
Go into your browser's settings and make sure it is set as "Default Browser" (do you have multiple browsers installed?)
Optionally, you can specify which browser to use: Process.Start(browser,url)
Can look up which browsers are installed via the registry.
I'm pretty sure the problem is that Windows doesn't which which program is the "default" browser. Not sure why tho. (have you recently un-installed a browser? Or anything related to your browser)
create a new .txt file and save it as a .html file on your desktop: which icon does it have? FireFox, IE, other?