Not all named file fields are provided via a behavior...

plone/app/versioningbehavior/modifiers.py

@@ -5,6 +5,7 @@
 from plone.behavior.registration import lookup_behavior_registration
 from plone.dexterity.interfaces import IDexterityContent
 from plone.dexterity.utils import iterSchemata
+from plone.dexterity.utils import resolveDottedName
 from plone.namedfile.interfaces import INamedBlobFileField
 from plone.namedfile.interfaces import INamedBlobImageField
 from Products.CMFCore.utils import getToolByName
@@ -170,6 +171,7 @@ def reattachReferencedAttributes(self, obj, attrs_dict):
         obj = aq_base(obj)
         for name, blob in six.iteritems(attrs_dict):
             iface_name, f_name = name.rsplit('.', 1)
+            # In case the field is provided via a behavior:
             # Look up the behavior via dotted name.
             # If the behavior's dotted name was changed, we might still have
             # the old name in our attrs_dict.
@@ -178,9 +180,10 @@ def reattachReferencedAttributes(self, obj, attrs_dict):
             # be found.
             try:
                 behavior = lookup_behavior_registration(iface_name)
+                iface = behavior.interface
             except BehaviorRegistrationNotFound:
-                return
-            iface = behavior.interface
+                # Not a behavior - fetch the interface directly
+                iface = resolveDottedName(iface_name)
             field = iface.get(f_name)
             if field is not None:  # Field may have been removed from schema
                 adapted_field = field.get(iface(obj))