cannot write setting file in the database folder

 

I was uploading the forum 9.6 on my web hosting site. When I launch the forum folder and select sql server 2005/2008 and entered all the credential, the connection test to the database server is successful. But when I click on Next, it shows me the error message saying the setting file in the forum\database folder is not writable. I use the online webfile control interface to set the security of that folder to be full control for network service and anonymous users. But the error persists. What is wrong with that? The backbone is windows server 2008 and sql server 2008. IIS support ASP 3.0 and ASP.NET 2.0. IIS shows as version 6 in their FAQ but I think it should be version 7 on my backend server.