Categorizing emails based on the subject

[Ludo]

and one last question (i Hope!)
I could manage to point the macro to the item I wanted (subject, sender, body, ...) but is it possible to make it point to the file name of an attached email?
i was expecting to have something like:

ElseIf InStr(1, olItem.Attachemnts, "[CAT1]", vbTextCompare) > 0 Then
    olItem.Categories = "[CAT1]"
    olItem.Save

But it doesn't seems to work and I couldn't find anything else on Google. Would you have any good address where to look that kind of stuff for my knowledge?