Steps to create Shared assembly

1. Create a new Class library file from .Net IDE.
   
2. Write the required code.
   
3. Compile the class library. It will produce a .dll at bin\debug\ folder which is called as an assembly.
   
4. In order to register an assembly with in a GAC, it is mandatory that the assembly should define with the strong name.
   

   To do, in the .Net Command prompt
   

   ..\>sn –k <filename>.snk
   

5. In IDE, through Solution Explorer ,open AssemblyInfo.cs and change [assembly: AssemblyVersion("1.0.*")] to [assembly: AssemblyVersion("1.0.0.0")]
   
6. Also, change [assembly: AssemblyKeyFile] to [assembly: AssemblyKeyFile(@"<strongNameFilePath>)]
   
7. Open a the class library file and write the required code, then rebuild the project.
   
8. Then register the assembly definition within GAC using gacutil command at .Net command prompt.
   

   ..\>gacutil –i <dll_file_path>
   

9. Verify at C:\Windows\Assembly, an entry of new dll exists.