XML validation

Hi,

I receive an xml which is showing the error "
INVALID List of errors:
[0] pathName=/ errorCode=NV-002 errorMessage=[ISC.0082.9002] Unable to retrieve root element
at pub.schema.validate" while validating. On checking the xml node with the schema, it seems to be valid.
What does this error mean? and how can we avoid it?

Thanks

The error message reference indicates that this means the document passed to validate is empty. Verify what is being passed to validate.

We are passing the xml node while validating against the schema. It is not empty. But i am still getting the error

Can you post a screen shot of your service at that step?