Hi, I have a site which is based on Zope and Plone, where users can shop around (shopping cart is stored in SESSION objects) and a separate part of the site (backend, Plone) where newsletters and such can be sent out. I have a problem however with duplicate emails being sent out to the subscribers, and this is most likely due to conflict errors being raised.. The event.log file says: 2008-02-18T21:05:23 INFO ZPublisher.Conflict ConflictError at /VirtualHostBase/http/www.site:80/VirtualHostRoot/levanger/plone/site_newsletter/nyhetsbrev-130208/testSendToMe: database conflict error (oid 0x92aa, class BTrees._OOBTree.OOBTree, serial this txn started with 0x0373d8eef99cf5bb 2008-02-18 21:02:58.503076, serial currently committed 0x0373d8f1624479aa 2008-02-18 21:05:23.031441) (58 conflicts (0 unresolved) since startup at Thu Jan 24 17:34:08 2008) Now, those errors aren't a big deal in themselves, but it is a problem when the system sends out duplicate mail messages to lots of visitors. I've seen some blurbs about deferring sending emails until the transaction has been completed, and I just discovered zope.sendmail which is said to defer sending emails until the transaction has succeeded. Is zope.sendmail a good choice? Will it work with Zope 2.9.8? Thanks, Morten