I have a macro that I would like to update every tab in the workbook, but I
can only get the one active sheet to update when I run the macro. I tried to
use two "FOR" staements but got an error. I want this macro to update every
sheet every time the workbook is opened. Here is my code. Any help would be
great as I rarely write macros so I am doing this by trial and error and
reading past posts. Thanks!

Sub Workbook_Open()
' This Macro will clear out the UNLOCKED cells of a sheet that is older
' than todays date by looking at the date cell in the spreadsheet
Dim cell As Range
With ActiveWorkbook
If Date Range("A1").Value Then
For Each cell In ActiveSheet.UsedRange
If Not cell.Locked Then cell.ClearContents
Next cell
End If
End With
End Sub