Plone Migration 4.3.4 to 5.0 Errors

Hi, i have upgrading from 4.3.7 to 5.0.2. In my buildout i set version.cfg to Index of /release/5-latest/ and the find-links option also. Now i get the following "Traceback" when i run the upgrade with "Dry Run" option in the zmi.

Dry run selected.
Traceback (most recent call last):
2016-02-04 15:09:33 ERROR plone.app.upgrade Upgrade aborted. Error:
Traceback (most recent call last):
File "/home/Development/Plone/Plone-5.0r1/buildout-cache/eggs/Products.CMFPlone-5.0.2-py2.7.egg/Products/CMFPlone/MigrationTool.py", line 268, in upgrade
step['step'].doStep(setup)
File "/home/Development/Plone/Plone-5.0r1/buildout-cache/eggs/Products.GenericSetup-1.8.1-py2.7.egg/Products/GenericSetup/upgrade.py", line 166, in doStep
self.handler(tool)
File "/home/Development/Plone/Plone-5.0r1/buildout-cache/eggs/plone.app.upgrade-1.3.20-py2.7.egg/plone/app/upgrade/v50/betas.py", line 544, in to50rc3
settings = registry.forInterface(IIterateSettings)
File "/home/Development/Plone/Plone-5.0r1/buildout-cache/eggs/plone.registry-1.0.2-py2.7.egg/plone/registry/registry.py", line 74, in forInterface
"for which there is no record." % (interface.identifier, name))
KeyError: 'Interface plone.app.iterate.interfaces.IIterateSettings defines a field checkout_workflow_policy, for which there is no record.'
2016-02-04 15:09:33 INFO plone.app.upgrade End of upgrade path, main migration has finished.
2016-02-04 15:09:33 ERROR plone.app.upgrade The upgrade path did NOT reach current version.
2016-02-04 15:09:33 ERROR plone.app.upgrade Migration has failed
2016-02-04 15:09:33 INFO plone.app.upgrade Dry run selected, transaction aborted

What should i do? Any ideas?

Ok, I found a solution. I delete 'checkout_workflow_policy' in the Plone 4.3.7 zmi-> portal_properties -> site_properties.
and now the upgrade works fine.