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Ugh, there's lots of crappy stuff going on about when to save the XML sitemap data from the user account form and when to save it because the $account object changes. I'm looking into this right now, but currently the per-user settings are not working on 7.x-2.x or 6.x-2.x.
This means you should not enable xmlsitemap_users until this is resolved. See issue
This XML file does not appear to have any style information associated with it. The document tree is shown below.
This just means that you are viewing the raw XML page. There is nothing wrong and you can ignore this warning. If you would like to enable a nicer viewing style for your XML sitemaps, you can enable the "Include a stylesheet in the sitemaps." option in admin/settings/xmlsitemap.
Use http://example.com/?q=sitemap.xml as your sitemap's URL or enable clean URLs. Please note that using clean URLs is highly recommended.
Invalid date - An invalid date was found. Please fix the date or formatting before resubmitting.- Parent tag: url
Most likely you are using PHP 5.1.1 or PHP 5.1.2, which introduced the new date/time constant DATE_W3C but doesn't include the required semicolon in the timezone separator. This bug has been fixed in PHP 5.1.3 and higher. See http://bugs.php.net/bug.php?id=36599.
If your site's URLs normally look like http://example.com/ but they are generated in the sitemap as http://www.example.com/ (or something other than expected) you probably need to set the $base_url variable in your site's settings.php file. The 6.x-2.x version has an option to set this variable at admin/settings/xmlsitemap. Clear the cache and run the cron to rebuild sitemap with new $base_url. See http://drupal.org/node/562404 or http://drupal.org/node/505232.
Error loading stylesheet: An XSLT stylesheet does not have an XML mimetype
See the previous answer about setting the $base_url variable in your site's settings.php.
Verification failed. Your verification file has the wrong content.
Google changed the method for verification which is not compatible with the 5.x and 6.x-1.x version of the XML sitemap engines sub-module. You should install and enable the Site verification module for your search engine verifications. This functionality is being deprecated from the XML sitemap engines sub-module.
- Performance issues
The current recommended 6.x-1.x and 5.x versions cause serious performance issues on sites that have large amounts of content to index into sitemap data. Disabling the module usually resolves the performance issues. See http://drupal.org/node/448000#comment-1534704 for details. Also note that the 6.x-2.x branch is a complete refactoring with considerations for performance, scalability, and reliability.
- Access Denied (403) errors when submitting to search engines.
Use of the "Submit the sitemap when content changes" checkbox can cause the search engines to give you Access Denied (403) or other errors because of the rate of submission. If your content is mostly static you may use this feature safely but if you have content that is changing with every cron.php run or user entry then the content will be submitted at the next user's page refresh. This was discussed at http://drupal.org/node/534460.
Other than the issues specified in the All versions section there are no other known issues.