How can I connect to SQL Server using (local)\INSTANCE_NAME?

I have a developer that is having trouble connecting to a SQL Server instance by entering the server name (local)\HIS_SERVER_INSTANCE into Visual Studio->Server Explorer. If he replaces (local) with his machine name, it connects fine. I have had similar issues before but they seemed to fix themselves. Does anyone know a fix for this?

EDIT:

We cannot use the machine name because our app contains connection strings with (local) in them.

Also, I've noticed something weird about his SQL Server install. Everyone else seems to get the SQL Server Service Manager showing in the lower right corner. I looked for this app in his startup folder and nothing was there. I then looked for the app on the system (C:\Program Files\Microsoft SQL Server\80\Tools\Binn\sqlmangr.exe) and it doesn't exist. Maybe 开发者_运维问答his system has bigger issues??

You can use .\HIS_SERVER_INSTANCE to get the same effect as using (local).