This issue is not resolved if you install your assembly to the global assembly cache, because the Add Reference dialog box is path-based and does not enumerate the components from the global assembly cache.
To display your assembly in the Add Reference dialog box, you can add a registry key, such as the following, which points to the location of the assembly
NOTE: You can create the this registry entry under the HKEY_LOCAL_MACHINE hive. This will change the setting for all of the users on the system. If you create this registry entry under HKEY_CURRENT_USER, this entry will affect the setting for only the current user.
Restart Visual Studio .NET after you have added the key.
If you install the .NET Framework 3.0 Service Pack 1 (SP1), the following registry subkey is added: