You use the word "selects"

Is user selecting from a menu of choices, like a Data Validation Dropdown
list or is user simply typing "yes" in a cell?

Either way, to get an actual pop up message you would need event code to
remind user.

This is a reminder only.

Private Sub Worksheet_Change(ByVal Target As Range)
Const myRange As String = "A1" ' "A1:A10" if a range
On Error GoTo endit
Application.EnableEvents = False
If Not Intersect(Target, Me.Range(myRange)) Is Nothing Then
If Target.Value = "yes" Then
MsgBox "You must fill in " & Target.Offset(0, 1).Address
End If
End If
endit:
Application.EnableEvents = True
End Sub

Right-click on the sheet tab and "View Code". Copy/paste the above into
that sheet module.

Edit to suit. Alt + q to return to Excel.


Gord Dibben MS Excel MVP



On Thu, 3 Dec 2009 17:17:01 -0800, Andrew Mogg
wrote:

Is there any way to have a pop up occur to inform user that to continue a
value must be entered into a certain cell. eg if user selects 'yes' the a pop
up flags them to enter a value in adjacent cell