Is there a simple way to get Excel to automatically execute a macro whenever a cell is changed?
The cell in question would be in Worksheet("BigBoard").Range("D2")
What I thought would be a simple Google inquiry is proving to be more complicated - every sample involved intersects (whatever those are) or color formatting or any other number of things that appear to be irrelevant.
Yes, this is possible by using worksheet events:
In the Visual Basic Editor open the worksheet you're interested in (i.e. "BigBoard") by double clicking on the name of the worksheet in the tree at the top left. Place the following code in the module:
Private Sub Worksheet_Change(ByVal Target As Range) If Intersect(Target, Me.Range("D2")) Is Nothing Then Exit Sub Application.EnableEvents = False 'to prevent endless loop On Error Goto Finalize 'to re-enable the events MsgBox "You changed THE CELL!" Finalize: Application.EnableEvents = True End Sub 
Insersect(rng1,rng2) returns the range where both input range "intersect". therefore, if the intersection of the changed cells and D2 is nothing, something else was changed and you don't want the macro to procede. BTW: If it solved your problem, please mark it as the solution by clicking on the checkmark!
Another option is
Private Sub Worksheet_Change(ByVal Target As Range) IF Target.Address = "$D$2" Then MsgBox("Cell D2 Has Changed.") End If End Sub I believe this uses fewer resources than Intersect, which will be helpful if your worksheet changes a lot.
In an attempt to find a way to make the target cell for the intersect method a name table array, I stumbled across a simple way to run something when ANY cell or set of cells on a particular sheet changes. This code is placed in the worksheet module as well:
Private Sub Worksheet_Change(ByVal Target As Range) If Target.Cells.Count > 0 Then 'mycode here end if end sub In an attempt to spot a change somewhere in a particular column (here in "W", i.e. "23"), I modified Peter Alberts' answer to:
Private Sub Worksheet_Change(ByVal Target As Range) If Not Target.Column = 23 Then Exit Sub Application.EnableEvents = False 'to prevent endless loop On Error GoTo Finalize 'to re-enable the events MsgBox "You changed a cell in column W, row " & Target.Row MsgBox "You changed it to: " & Target.Value Finalize: Application.EnableEvents = True End Sub I was creating a form in which the user enters an email address used by another macro to email a specific cell group to the address entered. I patched together this simple code from several sites and my limited knowledge of VBA. This simply watches for one cell (In my case K22) to be updated and then kills any hyperlink in that cell.
Private Sub Worksheet_Change(ByVal Target As Range) Dim KeyCells As Range ' The variable KeyCells contains the cells that will ' cause an alert when they are changed. Set KeyCells = Range("K22") If Not Application.Intersect(KeyCells, Range(Target.Address)) _ Is Nothing Then Range("K22").Select Selection.Hyperlinks.Delete End If End Sub 
