Im tyring to create a unique member id in code, and update the member table with member details. I get the following error:

Microsoft JET Database Engine error '80040e21'

Index or primary key cannot contain a Null value.

/Project/AddUser.asp, line 39

Could anyone please advise me on how to fix this error? thanks.

*--------------------------------------------------------------------


<%
  Dim rsUsers, strUserId
  Set rsUsers = Server.CreateObject("ADODB.Recordset")
  rsUsers.Open "Members", objConn, adOpenForwardOnly,adCmdTable
  if session("MemberId") <> "" then
    rsUsers.filter = "MemberId = '" & session("MemberId") & "'"
  else
    rsUsers.filter = "EmailAddress = '" & request. form("txtEmailAddress") & "'" &_
             "AND Password = '" & request.form("pwdPassword") & "'"
  end if

  rsUsers.AddNew
  strUserId = rsUsers("MemberId")
  strUserId = strUserId + 1
  rsUsers("MemberId") = strUserId

  rsUsers("TraderName") = request.form("txtTraderName")
  rsUsers("Password") = request.form("pwdPassword")
  rsUsers("Firstname") = request.form("txtFirstname")
  rsUsers("Surname") = request.form("txtSurname")
  rsUsers("EmailAddress") = request.form("txtEmailAddress")
  rsUsers("MobileNumber") = request.form("txtMobileNumber1")
  if Request.form("chkEmailUpdates") = "on" then
    rsUsers("EmailUpdates") = true
  else
    rsUsers("EmailUpdates") = false
  end if
  if request.form("chkSmsUpdates") = "on" then
    rsUsers("SmsUpdates") = true
  else
    rsUsers("SmsUpdates") = false
  end if
  rsUsers("CashBalance") = 100000
  rsUsers("PortfolioValue") = 100000
  rsUsers("Active") = true

  rsUsers.update

  Dim strName, strValue
  for each strField in rsUsers.fields
    strName = strField.Name
    strValue = strField.Value
    session(strName) = strValue
  next
  Session("blnValidUser") = True
  response.redirect "MyPortfolio.html"
%>

following are possible solutions:
1. You can use auto number of MS-Access, which will create autonumber itself.

2. I think u should remove the condition to get the auto number.

  rsUsers.AddNew
  strUserId = rsUsers("MemberId")
  strUserId = strUserId + 1
  rsUsers("MemberId") = strUserId

 What is happening is it gets no record if there is no match (with filter), and so why the error.



Om Prakash