The following macro works partially...

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Private Sub Workbook_Open()

On Error GoTo Workbook_Open_Error

If Worksheets("Audit").Range("E2").Value = "New" Then
Worksheets("Audit").Range("A2").Value = Application.UserName
Worksheets("Audit").Range("B2").Value = Date
Worksheets("Audit").Range("C2").Value = Time
Randomize
Worksheets("Audit").Range("D2").Value = Rnd()

....up to here, but the next two lines don't do anything. They are supposed
to protect with a random password, and then hide the sheet....

Worksheets("Audit").Protect Password:="A" & Int(Rnd() * 10000000000#)
Worksheets("Audit").Visible = False
End If

GoTo Workbook_Open_Complete

Workbook_Open_Error:
MsgBox "Error in Workbook_Open"

Workbook_Open_Complete:

End Sub
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Can someone give me some clues? I'm sure this worked yesterday!