IIRC, you cannot/should not create folder items in the application's folder. Instead, you should create the folder items in the C:\Documents and Settings\All Users\Application Data\[Your Company] or C:\Documents and Settings\[User Name]\Application Data\[Your Company] folder.
Seems that's the problem !
But WHY on Vista (and only on Vista, nor Win XP now Mac OS X) i cannot create folder items in the application's folder ?
i've that code that runs ok on Mac and on Win Xp
Dim subfolder as FolderItem
subfolder = GetFolderItem("Test")
TestDB = New REALSQLDatabase
TestDB.databaseFile = GetFolderItem("/TestProgram/TestDB.rsd")