Excel guru's needed badly...

Private Sub Worksheet_SelectionChange(ByVal Target As Range)
Static LastCell As Range
If Target.Cells.Count > 1 Then
Exit Sub
End If
If LastCell Is Nothing Then
Set LastCell = Target
End If
If LastCell.Address(False, False) = "F5" Then '<<< CHANGE
If LastCell.Value = vbNullString Then
Application.EnableEvents = False
LastCell.Select
MsgBox "Enter a Value!"
Application.EnableEvents = True
End If
Set LastCell = Range("F5") '<<< CHANGE
Else
Set LastCell = Target
End If
End Sub


I used this above code to build some VB into a spreadsheet I'm building... I'm not super familiar with macros or editing the VB side of things..

I'm trying to expand this code to populate with this message for each subsequent sell...

For instance, I've got Columns A, B, C, D, E, F.

If I select something from the drop down in column A, I want it to be required to put something in column C on the same row.

The code I put in seems to only work for the first cell in the column.. so I get the error if I delete the text, but no notification if I choose a value in A, and then click somewhere else.... I want it to be required to put a value in C as soon as you select a value in A.

Basically, *ANY* value in A will require entry into C... If A has a value, C cannot be left blank and an error will pop-up.

Any ideas?

TIA.