Restart your machine after installing Fulltext service for MS SQL Server Express 2005

I had MS SQL server express 2005 installed without Fulltext index support. When I needed it, I installed it, created a catalog, an index, and started change tracking, then I tried to make simple CONTAINS query, nothing returned.
I worked with FTS many times and for years (mainly with SQL Server 2000). It was hard to retry many times to get any result with not good.
I tried many times to drop the index, start full population, incremental population. Nothing worked.
I looked into the event viewer, I found this error:

Errors were encountered during full-text index population for table or indexed view '[dbname].[dbo].[TableName]', database ''[dbname].[' (table or indexed view ID '1550628567', database ID '7'). Please see full-text crawl logs for details.

I looked in the fulltext log ( located at : installationpath/MSSQL.1\MSSQL\LOG\SQLFTxxxxxxxxxx.LOG.x) , this info existed in error logs:

Error '0x80040e09' occurred during full-text index population for table or indexed view '[dbname].[dbo].[TableName]' (table or indexed view ID '1550628567', database ID '7'), full-text key value 0x00000001. Attempt will be made to reindex it.
The component 'sqlfth90.dll' reported error while indexing. Component path 'C:\Program Files\Microsoft SQL Server\90\COM\sqlfth90.dll'.

After searching for such error, I found that after installing fulltext service on MS SQL Express 2005, the machine must be restarted, and that this is mentioned in the ReadMe!!

If only we read the manual !!!!