I don't think that you have all validation rules turned off. I would guess that Item no has "unique values" specified as a validation field option and it's the source of your validation error message. And I can see that option specified in your screen shot.
While you can clear that check box, you might instead want to consider why you have a record with a non-unique item no. if this field should be unique in the table where it's defined.
Thank you very much for the quick reply. I have to apologize for my oversight in that the item field was duplicated and named something else in the process of developing a new feature and all of the same validation and message was on. Sorry for the fire drill!!