corregendo la riga mi appare
mi appare a video:
SELECT username FROM 1 WHERE username=''
questo e lo script
<%
Dim Conn
Set Conn=Server.CreateObject("ADODB.Connection")
Conn.Open "driver={Microsoft Access Driver (*.mdb)};dbq="& Server.Mappath("/marinodiprinzio/mdb-database/utenti.mdb")
Username=Request.Form("username")

rs=server.createobject("adodb.recordset")
strSQL="SELECT username FROM iscritti WHERE username='"& username &"'"
response.write strsql:response.end
if not rs.EOF then
response.write("ok")
else
response.write("username assente")
end if
rs.Close
set rs=nothing
%>