I get this error:
EntityMetadataWrapperException: Unknown data property field_comment_ref. in EntityStructureWrapper->getPropertyInfo() (line 339 of */sites/all/modules/entity/includes/entity.wrapper.inc)
whenever I try to enter a comment on a node

Comments

+1

me too...so what u have done to fix this???

I got this error to , trying to post a comment in advanced forums.
In my case , It had something to do with message-notify-example.
Disabling it, and I can post comments again, and no error.