element must be a full URI

The specified value is not a full URI, or is mal-formed.

If this is a link to a web page, make sure to include the "http://" at the beginning. If you've already done that, it's possible that the URI contains an invalid character. A complete list of acceptable characters can be found in RFC 3986.

If this is a mailing address, make sure to include the "mailto:" at the beginning.

The data in link elements must begin win an IANA-registered URI scheme