下面是ChkPwd.asp
--------------------------
<!-- #include file="Conn.asp"-->
<%
 If IsEmpty(Session("Passed") Then
   Session("Passed") = False
 End If
 
 If Session("Passed") = False Then
   UserName = Request.Form("UserName")
   UserPwd = Request.Form("UserPwd")
 
   If UserName = "" or UserPwd = "" Then
     Errmsg = "请输入用户名或密码"  
   Else
     Set rs = Server.CreateObject("ADODB.Connection")
     Set rs.ActiveConnection = Conn
     rs.CursorType = 3
     rs.Open "SELECT * FROM Users WHERE UserName='" & UserName & "'"
     If rs.EOF Then
       Session("Errmsg") = "用户名不存在"
     Else
       If UserPwd <> rs.Fields("UserPwd") Then
      Session("Errmsg") = "用户密码不正确"
    Else
      Errmsg = ""
      Session("UserName") = rs.Fields("UserName")
      Session("UserPwd") = rs.Fields("UserPwd")
      Session("Errmsg") = ""
    End If
     End If
   End If
   Response .Redirect("index.asp")
 End If      
%>

在首页index.asp
一开始我是这样写的
if Session("Errmsg")<>"" then
Response.write "游客你好,请登陆"

发现有问题
后面无意中改成
if Session("Errmsg")="" then
response.Write "游客你好，请登陆"
else
response.write Session("Errmsg")
Session("Errmsg")=""
end if
就对了

本来在ChkPwd.asp
如果登陆成功，设Session("Errmsg")=""

为什么在首页调用的时候
if Session("Errmsg")="" then
response.Write "游客你好，请登陆"
这个才是对的
而不是
if Session("Errmsg")<>"" then
Response.write "游客你好,请登陆"

If IsEmpty(Session("Passed") Then
 缺少）

if Session("Errmsg")<>"" then
Response.write "游客你好,请登陆"



游客没有经过ChkPwd.asp处理  Session("Errmsg")自然=""

给你说个简单的:

if Not isEmpty(request.form("submit")) then
set conn=server.createobject("adodb.connection")
conn.open "连接字符传"
name=request.form("name")
pwd=request.form("password")
sql="select * from where name='" &  name &"' and password='" & pwd &"'"
set rs=conn.execute(sql)
if Not rs.eof then
    Response .Redirect("index.asp")
end if
end if