thank's Mitchel for this quick answer!
now, i thnk i understand what you try to explain to me, sorry i'm french so i have to read your answer couple of time before understand well :-)
another think i'm not undertanding in the dotnetnuke setup is about the SQL database
after my installation, i can see in SQL Server Express/data/.../mydb.mdf and mydb.log.ldf are existing.
also 2 others file exist and from default in dotnetnuke 4.5.5, they are cal Database.mdf and Database.log.ldf
wich file are good and do i have to copy over ?
I'v try to move my site in doing a export database from Sql Express Studio of the "mydatabase" without success
I' dont know how to export "Database.mdf" with Sql Studio Express
sorry if all those sentences abouve are not clear, i repeat, i just try my best in english :-(
bye