have you ever come across this error when you try to run your website from localhost??

and when I looking for the real problem in production server, I understand that version. NET Framework that I use is 4.0. for that I need to replace the actual version .NET Framework version 2.0.

Here is a short step to change. NET version:

1. Open your IIS ( for this article i use IIS 8)
2. Click your Application Pool (Before that, make sure your dedicated pool was tick on your server) and search your domain name.
    You'll find that your .NET Framework version is 4.0. (this version is default by plesk control panel 11)
3. Click Basic Setting.

4. then change .NET Framework version to 2.0 - Ok

5. Yeah.. now you can reload your web browser and check your website.