Outlook VBA Code stops firing after some time - vba

Question

The code below works perfectly:
Option Explicit
Dim myOlApp As New Outlook.Application
Public WithEvents myOlInspectors As Outlook.Inspectors
Private Sub Application_Startup()
Initialize_handler
End Sub
Public Sub Initialize_handler()
Set myOlInspectors = myOlApp.Inspectors
End Sub
Private Sub myOlInspectors_NewInspector(ByVal Inspector As Outlook.Inspector)
Dim msg As Outlook.MailItem
If Inspector.CurrentItem.Class = olMail Then
Set msg = Inspector.CurrentItem
If msg.Size = 0 Then
'MsgBox "New message" ' TEST LINE
msg.CC = "email#email.com"
End If
End If
End Sub
However, after a few hours of works. It suddenly stops firing (and I don't get any error).
Is there something I missunderstand about the code?
Is there something about Outlook.Inspectors, that makes it stop launching for some reason?

Answer 1

Your event method may fail if no item is currently open.
To add a CC recipient, you should do something like
Set myRecipient = msg.Recipients.Add("email#email.com")
myRecipient.Type = olCC
Documentation

Answer 2

Most probably the event is fired properly, but you have got an error in the code at runtime. The NewInspector event is not the best place for getting the CurrentItem property:
Private Sub myOlInspectors_NewInspector(ByVal Inspector As Outlook.Inspector)
Dim msg As Outlook.MailItem
If Inspector.CurrentItem.Class = olMail Then
Set msg = Inspector.CurrentItem
If msg.Size = 0 Then
'MsgBox "New message" ' TEST LINE
msg.CC = "email#email.com"
End If
End If
Especially the following line of code could raise an error at runtime:
If Inspector.CurrentItem.Class = olMail Then
Instead, consider using the first Inspector`s Activate event which is fired when an inspector becomes the active window, either as a result of user action or through program code. So, in the first Activate event you could get item's properties without a problem.
Also you may consider adding On Error statement to the code so you could be aware why the event "is not fired".