Error after plone.app.multilingual 5.0.7

[gp54321]

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How to fix error related to 'portal_factory'

Hi, everyone. I have had a problem while trying to install the add-ons named Multilingual ArchType ... which is a standard one, it comes with Plone 5. With the result that the error message: "AttributeError('portal_factory',) (Also, the following error occurred while attempting to render the standard error message, please see the event log for full details: portal_factory)" poped up. After that plone page did not show up again. I still can visit the zope's ZMI page but I do not know how to corre…