I am having issues with this as well. When I try to validate it I get the following. You can see the 404 errors below.
Schema validating with XSV 2.10-1 of 2005/04/22 13:10:49
Target: [external links are visible to admins only]
(Real name: [external links are visible to admins only]
Length: 1480 bytes
Last Modified: Sat, 28 Apr 2007 13:37:42 GMT
Server: Microsoft-IIS/6.0)
docElt: {http://www.sitemaps.org/schemas/sitemap/0.9}urlset
schemaLocs: [external links are visible to admins only] -> [external links are visible to admins only]
The schema(s) used for schema-validation had no errors
The target was not assessed
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Low-level XML well-formedness and/or validity processing output
Error: can't retrieve "[external links are visible to admins only]": 404 Not Found
Error: can't retrieve "[external links are visible to admins only]": 404 Not Found
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Schema resources involved
Attempt to load a schema document from [external links are visible to admins only] (source: schemaLoc) for [external links are visible to admins only], failed:
couldn't open
Attempt to load a schema document from [external links are visible to admins only] (source: docElt) for [external links are visible to admins only], failed:
couldn't open
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