Method VBProject of _workbook Failed

I ran recently ran an old bit of Excel VBA in Excel 2010 which automatically adds the Microsoft Scripting Runtime to the workbook for me. Rather annoyingly, I was getting a Method VBProject of _workbook Failed error.

I solved this by going into the Options > Trust Center > Trust Centre Settings... Choosing Macro Settings and then checking the Trust access to the VBA project object model checkbox.

The code to add the reference in case that helps too ;)

Public Sub SomeMethod()

    AddReference "C:\WINDOWS\system32\scrrun.dll"

End Sub

Private Sub AddReference(sFile As String)
Dim i As Integer
Dim bFound As Boolean

    bFound = False
    For i = 1 To ActiveWorkbook.VBProject.References.Count
        If ActiveWorkbook.VBProject.References.Item(i).FullPath = sFile Then
            bFound = True
            Exit For
        End If
    Next i
    If Not bFound Then
        ActiveWorkbook.VBProject.References.AddFromFile sFile
    End If
End Sub