后台登陆后一片空白不能跳转

<meta http-equiv="Content-Type" content="text/html; charset=gb2312">这行去掉后正常，
如果编码为gb2312 显示为空白，改成UTF-8出现错误，报未结束的字符串常量
这不知道是什么原因？
希望老师们指点, 万分感谢！

<meta http-equiv="Content-Type" content="text/html; charset=gb2312">

<!--#include file="../inc/Fzwlt_AdminConn.asp"-->

<!--#include file="images/login/md5/md5.asp" -->

<!--#include file="images/login/md5/CFS.asp" -->

<%

if trim(request("OK"))="1" then

Response.Cookies("Fzwlt")("strUsername") = Trim(request("username"))

Response.Cookies("Fzwlt")("strPassword") = trim(request("password")) 

Response.Cookies("Fzwlt")("OKCookie")=trim(request("OK"))

'Response.cookies("Fzwlt").expires=date+365

Response.Cookies("Fzwlt").Expires=DateAdd("y",30,Now())

%>

<%

Dim DBC,RsLoginObj,RsLogObj

Dim UserName,UserPass,VerifyCode,System,SqlLog,SqlLogin,Url

Url = Request("UrlAddress")

if Url = "" then

	Url = "Fzwlt_MainFrame.asp"

end if

'Response.Write(Url)

'Response.End



UserName = Replace(Trim(Request.Form("UserName")),"'","''")

UserPass1 = CfsEnCode(Replace(Trim(Request.Form("Password")),"'","''"))

VerifyCode = Replace(Trim(Request("verifycode")),"'","")

UserPass=md5(UserPass1)

if UserName = "" or  UserPass = "" then 

	Response.Redirect("Fzwlt_Errorp.asp?ErrDescription=用户名和密码不能为空！")

	Response.End

end if



if Instr(request.form("UserName"),"=")>0 or Instr(request.form("UserName"),"%")>0 or Instr(request.form("UserName"),chr(32))>0 or Instr(request.form("UserName"),"?")>0 or Instr(request.form("UserName"),"&")>0 or Instr(request.form("UserName"),";")>0 or Instr(request.form("UserName"),",")>0 or Instr(request.form("UserName"),"'")>0 or Instr(request.form("UserName"),",")>0 or Instr(request.form("UserName"),chr(34))>0 or Instr(request.form("UserName"),chr(9))>0 or Instr(request.form("UserName"),"")>0 or Instr(request.form("UserName"),"$")>0 then

	response.write"<script>alert('错误提示信息!\n\n用户名或密码不能在非法字符！点击确定返回重新输入！');javascript:history.go(-1);</script>"

	response.End()

end if



if  VerifyCode <> CStr(Session("GetCode"))  then 

	response.write"<script>alert('错误提示信息!\n\n验证码错误！点击确定返回重新输入！');javascript:history.go(-1);</script>"

	Response.End

end if

if request("verifycode")="" then

	response.write"<script>alert('错误提示信息!\n\n请输入验证码！点击确定返回重新输入！');javascript:history.go(-1);</script>"

	Response.End

elseif Session("GetCode")="9999" then

	Session("GetCode")=""

elseif Session("GetCode")="" then

	response.write"<script>alert('错误提示信息!\n\n请不要重复提交！点击确定返回重新输入！');javascript:history.go(-1);</script>"

	Response.End

elseif cstr(Session("GetCode"))<>cstr(trim(request("verifycode"))) then

	response.write"<script>alert('错误提示信息!\n\n你输入的验证码和系统产生的不一致！点击确定返回重新输入！');javascript:history.go(-1);</script>"

	Response.End

end if

   Session("GetCode")=""

set RsLoginObj = server.CreateObject ("ADODB.RecordSet")

SqlLogin = "select * from Fzwlt_Admin where UserName='"&UserName&"' and  password='"&UserPass&"'"

RsLoginObj.Open SqlLogin,Conn,1,1

Session("Fzwlt_flag")=RsLoginObj("Fzwlt_flag")

Session("loginnos")=RsLoginObj("loginnos")

Session("loginip")=RsLoginObj("loginip")

Session("Csny")=RsLoginObj("Csny")

Conn.Execute("Update [Fzwlt_Admin] Set Csny='"&now()&"',loginnos=loginnos+1,loginip='"&Request.ServerVariables("REMOTE_ADDR")&"' Where UserName='"&UserName&"'")



System = Request.ServerVariables("HTTP_USER_AGENT")

if Instr(System,"Windows NT 5.0") then

	System = "Win2000"

elseif Instr(System,"Windows NT 5.2") then

	System="Win2003"

elseif Instr(System,"Windows NT 5.1") then

	System = "WinXP"

elseif Instr(System,"Windows NT") then

	System = "WinNT"

elseif Instr(System,"Windows 9") then

	System = "Win9x"

elseif Instr(System,"unix") or instr(System,"linux") or instr(System,"SunOS") or instr(System,"BSD") then

	System = "类Unix"

elseif Instr(System,"Mac") then

	System = "Mac"

else

	System = "Other"

end if



if Not RsLoginObj.EOF then

   if RsLoginObj("Lock")=1 then

	response.write"<script>alert('错误提示信息!\n\n你的帐号已锁定或无权进入！\n\n点击确定返回！');javascript:history.go(-1);</script>"

	Response.End

   end if

   Session("UserName") = UserName

   Session("PassWord") = UserPass

   Session("AdminID") = RsLoginObj("AdminID")

   Response.Cookies("Foosun")("UserName") = UserName

   Response.Cookies("Foosun")("Password") = UserPass

   Set RsLogObj = Server.Createobject("adodb.recordset")

   SqlLog = "select * from Fzwlt_Log"

   RsLogObj.open SqlLog,Conn,3,3

   RsLogObj.addnew

   RsLogObj("LogUser")=UserName

   RsLogObj("LogIP")=request.ServerVariables("Remote_Addr")

   RsLogObj("OS")=System

   RsLogObj("Result") = 1

   RsLogObj("Csny") = now()

   RsLogObj.update

   RsLogObj.close

   set RsLogObj = Nothing

   Response.Redirect(Url) 

   Response.End

else

   set RsLogObj = Server.Createobject("adodb.recordset")

   SqlLog = "select * from Fzwlt_Log"

   RsLogObj.open SqlLog,Conn,3,3

   RsLogObj.AddNew

   RsLogObj("LogUser") = Request.Form("UserName")

   RsLogObj("LogIP") = request.ServerVariables("Remote_Addr")

   RsLogObj("OS") = System

   RsLogObj("Errorpas") = Request.Form("Password")

   RsLogObj("Result") = false

   RsLogObj("Csny") = now()

   RsLogObj.update

   RsLogObj.close

   set RsLogObj = Nothing

	response.write"<script>alert('错误提示信息!\n\n非法登录, 请检查用户名和密码的是否正确！\n\n点击确定返回重新输入！');javascript:history.go(-1);</script>"

	Response.End

end if

%>