How to: Change an Assembly Name (Visual Basic, C#)

The Assembly Name property of an application determines the name that will be used for the compiled application. For example, setting the Assembly Name to “MyApplication” for a Windows-based application would result in an executable file named MyApplication.exe. The Assembly Name defaults to the project name; it can be changed on the Application page of the Project Designer.

To change the Assembly Name property

  1. With a project selected in Solution Explorer, on the Project menu, click Properties.
  2. Click the Application tab.
  3. In the Assembly Name field, type the name for your application.

Note
Although the default value of the Assembly Name is the same as the project name, the two are unrelated; changing the project name does not change the Assembly Name and changing the Assembly Name does not change the project name.

http://msdn.microsoft.com/en-us/library/f0c12ze9.aspx