Microsoft OLE DB Provider for ODBC Drivers error '80004005'

[Microsoft][ODBC Driver Manager] Data source name not found and no default driver specified

/modulo/doadd.asp, line 22

Il codice della pagina:

20 Else
21 Set conn = Server.CreateObject("ADODB.Connection")
22 conn.open "sitesearch","",""
23 Set Session("sitesearch_conn") = conn
24 End If