如何用Access加密页面？

<%
userid = request("userid")
userpass = request("userpass")

set conn = server.createobject("adodb.connection")
dbpath = server.mappath("userinfo.mdb")
conn.open "driver={microsoft access driver (*.mdb)};dbq=" & dbpath

userid=trim(userid)
userpass=trim(userpass)
sql="select * from [userinfo]"
set rs=conn.execute(sql)
while not (rs.bof or rs.eof )
  if userid=trim(rs("用户名")) and userpass=trim(rs("口令")) then
    flag = "1"
end if
rs.movenext()
wend
if flag = "1" then
rs.close()
else
rs.close()
response.write "<center>噢,此用户不存在或口令不正确!请重新输入...
</center><p align='center'>

<a href='javascript:history.go(-1);'>点击这儿返回上页.</a>"
response.end
end if
conn.close
%>