Hi, the data converter for objects raises a ValueError if it can't find a factory. This is caught by the validation machinery around it and displayed to the user with 'There were errors'. This isn't helpful as the user isn't told whats going on and he won't be able to do anything about it. The code pattern seems that this is only a synthesized version of what exception the component architecture would raise. Thus the error should appear as an application error (visible in the error log) as this situation needs to be dealt with by a programmer. Objections for changing this? Christian -- Christian Theune · ct@gocept.com gocept gmbh & co. kg · forsterstraße 29 · 06112 halle (saale) · germany http://gocept.com · tel +49 345 1229889 7 · fax +49 345 1229889 1 Zope and Plone consulting and development