How to determine what components are installed for SQL 2005 Express

We have serveral app groups that have installed SQL 2005 Express, but each group have installed different components. How can I determine, specifically if the following components were previously installed.

ADDLOCAL=SQL_Engine
ADDLOCAL=SQL_FullText
ADDLOCAL=RS_Server

And if not installed re-install with the missing component?

Thanks

Tony Z

There are two approaches you can check.

1. You can go Control Panel --> Add/Remove Program. Select the SQL Express entry and choose Update. Then you can see the components installed.

2. On x86 machine, check the regsigry key HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft SQL Server\MSSQL.1\Setup : FeatureList

On x64 machine, check the corresponding WOW registry key.