Odoo Warning - Validation Error
<p>I've just installed <strong>odoo v9</strong> on my Ubuntu server. It seems OK but if I update quantity on hand in product, it gives me this error. Can anyone help me resolve this?</p>

<blockquote>
  <p>The operation cannot be completed, probably due to the following:</p>
  
  <ul>
  <li>deletion: you may be trying to delete a record while other records still reference it</li>
  <li>creation/update: a mandatory field is not correctly set</li>
  </ul>
  
  <p>[object with reference: weight_uom_id - weight.uom.id]</p>
</blockquote>