I just encountered a problem which scares me to some extent. I have developed my own product with my own set of ZClasses. In my Products folder I had my product, some other products and the PTKBase product. The version of the PTK was from a couple of weeks ago (or so). Yesterday I retrieved the latest PTK stuff from the CVS repository and updated the contents of my products directory with this version of PTK. Suddenly existing instances of ZClasses that I had created previously, were appearing as broken. They apparently couldn't find their product. I was confused by this, because I was able to add new instances of my ZClasses. After posting a message to the zope mailing list, I received a reply which suggested that perhaps a product unrelated to my product was causing a problem. Having nothing else to lose, I replaced my PTKBase with the old version of PTKBase. After restarting Zope my broken ZClasses were once again functioning. My question is this, why should a product unrelated to my product cause problems with my ZClasses? I feel a bit uncomfortable with the notion that one product can seemingly affect another. I don't believe any of my code relied on anything relating to the PTK. Can someone explain what might have happened? Thanks. James W. Howe mailto:jwh@allencreek.com Allen Creek Software, Inc. pgpkey: http://ic.net/~jwh/pgpkey.html Ann Arbor, MI 48103