错误类型：
Microsoft OLE DB Provider for ODBC Drivers (0x80004005)
[Microsoft][ODBC 驱动程序管理器] 未发现数据源名称并且未指定默认驱动程序
/asp3/include/cod_ado.inc, 第 4 行

浏览器类型：
Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1)

网页：
GET /asp3/problem.asp
高手帮帮我啊
问题补充：这是提示错误的include/cod_ado.inc的代码
<%
sub cod_AdoOpen(objConnection, rsCoursesList,dsn,rss)
Set objConnection = Server.CreateObject("ADODB.Connection")
objConnection.Open dsn
Set rsCoursesList = Server.CreateObject("ADODB.Recordset")
rsCoursesList.ActiveConnection = objConnection
rsCoursesList.CursorLocation = adUseClient
rsCoursesList.CursorType = adOpenForwardOnly
rsCoursesList.LockType = adLockReadOnly
rsCoursesList.Source = rss
rsCoursesList.Open
end sub
sub cod_AdoClose(objConnection, rsCoursesList)
rsCoursesList.close
objConnection.close
set rsCoursesList = nothing
set objConnection = nothing
end sub
%>

高手告诉我到底是什么原因啊，跪求了