guid must be a full URL, unless isPermaLink attribute is false


By default, the guid element specifies a permanent link for an item, the value must be a full URL (for example, starting with "http://").

URIs (such as tag: URIs), as opposed to URLs, only identify, not locate, items, and are not suitable for permalinks.


If you are using the guid element as a permanent link, make sure the value is a full URL, that could be followed directly in a browser.

If you are using the guid element simply as a unique identifier (and not a link to the item), then the value can be whatever you want, but you must include the attribute isPermaLink="false" in the guid tag.

These are valid guids:

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