Simple Access login form code

loginform.vb

' Blank Usernames
If IsNull(cboUsername) Or cboUsername = "" Then
    MsgBox "Enter Username", vbOKOnly, "Required Data"
    cboUsername.SetFocus
    Exit Sub
End If

' Blank Passwords
If IsNull(txtPassword) Or txtPassword = "" Then
    MsgBox "Enter Password", vbOKOnly, "Required Data"
    txtPassword.SetFocus
    Exit Sub
End If

' Password Check
If txtPassword.Value = DLookup("Password", "tblEmployees", "[ID]=" & cboUsername.Value) Then
    MsgBox "Correct Password", vbOKOnly, "Login Successful"
    Exit Sub
Else
    MsgBox "Incorrect Password!  Please try again.", vbExclamation, "Login Failed"
    txtPassword.SetFocus
    Exit Sub
End If