Can some one please help me with; I'm new to this...

If Me.txtPassword = DLookup("strUserPassword", "tblUsers", "[AidUser]=" & txtNetUser.Value) Then
AidUser = Me.txtNetUser.Value

DoCmd.Close acForm, "frmStartup", acSaveNo
DoCmd.OpenForm "frmUnitSelect"
Else
MsgBox "Password Invalid. Please Try Again", vbOKOnly, "Invalid Entry!"
Me.txtPassword.SetFocus
End If

***Background Info:***
-txtPassword is a Text Box for User Passwords
-strUserPassword is a Field in tblUsers
-AidUser is an Autonumber field
-txtNetUser is a text box that autofills the user name from seperate Function

Try

If nz(Me.txtPassword, "None Supplied") = Nz(DLookup("[strUserPassword]", "tblUsers", "[AidUser] = '" & Me.txtNetUser & "'"),"None Found") Then

First, if the password is a string, you need the single quote delimiter ' in the DLookUp.

Second, I used the Nz function so that if nothing is supplied and/or nothing is found, you get no runtime error messages, but the "password" is rejected and you still get your rejection message.

Oh, and welcome to P2P!

No luck.....

Run-time error '3464':
Data Type Mismatch in criteria expression.
thank you for the welcome, not sure if this will help but here is the code that fills the Username box "txtNetUser"



Public Declare Function apiGetUserName Lib "advapi32.dll" Alias "GetUserNameA" _
(ByVal lpBuffer As String, nSize As Long) As Long


Function fOSUserName() As String
On Error GoTo fOSUserName_Err

Dim lngLen As Long, lngX As Long
Dim strUserName As String

strUserName = String$(254, 0)
lngLen = 255
lngX = apiGetUserName(strUserName, lngLen)

If lngX <> 0 Then
fOSUserName = Left$(strUserName, lngLen - 1)
Else
fOSUserName = ""
End If


fOSUserName_Exit:
Exit Function

fOSUserName_Err:
MsgBox Error$
Resume fOSUserName_Exit
End Function

Hi Devilboy13

Here is a code that I have use for a username & Password:
You will need to create a table with the following fields: UserName and Pass, will call this table tblUser. Then create a form with a username and password fields and add a submit and cancel button.

Let me know if you get stuck and I can send you some more instructions.

Cheers
Hennie


Private Sub CancelButton_Click()
DoCmd.RunCommand acCmdExit
End Sub

Private Sub okButton_Click()
Dim rs As ADODB.Recordset
Set rs = New ADODB.Recordset
 If IsNull(Me.UserTxt) Then
   MsgBox "Please enter a valid user name.", vbExclamation, "Error"
   Me.UserTxt.SetFocus
   Exit Sub
 ElseIf IsNull(Me.PassTxt) Then
   MsgBox "Please enter a valid password.", vbExclamation, "Error"
   Me.PassTxt.SetFocus
   Exit Sub
 End If
  rs.Open "SELECT * FROM tblUser WHERE(UserName = """ & Me.UserTxt & """ AND Pass = """ & Me.PassTxt & """)", _
   CurrentProject.Connection, adOpenKeyset, adLockOptimistic
    If rs.EOF Then
      MsgBox "Invalid user name or password. Please try again.", vbExclamation, "Error"
      Me.UserTxt.SetFocus
     Exit Sub
    End If
 MsgBox "Login Successful.", vbInformation, "Confirm!"
 DoCmd.Close
Exit Sub
End Sub

Thanks that worked... You are a life saver...