Notice! This page describes the nature of the error using a hypothetical example and not the erroneous data of the input test file. You should however be able to apply this information to your error case.
Error description
'<' is not allowed to be used in attribute value.
Example:
It is not allowed to given lower than character in attribute value. You have to remove the character.
<PstlAdr Ctry="FI">
Error message given by the service:
"Unescaped '<' not allowed in attributes values"