Hi Sascha, thanks for your reply. It solved part of the problem.

look at the message from Gidon a couple of days ago. Maybe you have the same problem that we had: Old ZClasses wouldn't move over or import into 2.6, because something has changed in the interfaces. Gidons solution was to remove entries in the subobjects, then export and re-import the ZClasses. Afterwards recreate the entries for subobjects.

It works for the three Zclasses that Zope didn't import before. I'm not having that long error message about the "pickled data" anymore, but I'm still having this one: ------ 2002-11-06T10:37:14 ERROR(200) Zope Couldn't install OFSP Traceback (innermost last): Module OFS.Application, line 700, in install_product - __traceback_info__: OFSP Module ZODB.Transaction, line 222, in commit Module ZODB.Transaction, line 195, in commit Module ZODB.Transaction, line 256, in _commit_objects Module ZODB.Connection, line 389, in commit - __traceback_info__: (('intSet', 'intSet'), '\x00\x00\x00\x00\x00\x00\x08:', '') Module ZODB.FileStorage, line 705, in store ConflictError: database conflict error (oid 000000000000083a, serial was 0348a51f52d8776e, now 0000000000000000) ------ 2002-11-06T10:37:16 ERROR(200) Zope Couldn't install ZCatalog Traceback (innermost last): Module OFS.Application, line 700, in install_product - __traceback_info__: ZCatalog Module ZODB.Transaction, line 222, in commit Module ZODB.Transaction, line 195, in commit Module ZODB.Transaction, line 256, in _commit_objects Module ZODB.Connection, line 389, in commit - __traceback_info__: (('intSet', 'intSet'), '\x00\x00\x00\x00\x00\x00\x0e\xb6', '') Module ZODB.FileStorage, line 705, in store ConflictError: database conflict error (oid 0000000000000eb6, serial was 0348a51f6ab4c9a2, now 0000000000000000) ------ What could be the problem? Thanks in advanced, Josef.