Same issue here – all sitemap pages are working but the tags link results in 404 error. I have only about 20 tags, and so the file size cannot be the problem… My XML map address is this: http://www.bpmstr.com/sitemap_index.xml …Did you manage to solve this? A reply would be valuable – thanks.
Update: the Tag Sitemap now works but required a strange tweak. Perhaps anyone knows why and how this is important. So… All my tags have custom WordPress SEO settings – SEO title and SEO description. These are blank by default but can be added on Edit Tag page for each tag I have. Prior to testing my tag sitemap and learning that it wasn’t generating, I set up all my tags to have an SEO title and description. And I now determined that with these custom descriptions Yoast does NOT generate the tag sitemap, UNLESS each such tag has the “Include in sitemap?” option set to “Always Include”. By default, this setting is on “Auto Detect”, and this is the root of the situation: To get Yoast to generate the tag sitemap, you must either (a) leave the SEO title and description of your tags blank or (b) change the value of “Include in Sitemap?” field from “Auto Detect” to “Always Include”. In fact, if you had a bunch of tags and half of them had the custom title/description and the other half didn’t *and* all of them were set to Auto Detect, then the resulting tag sitemap would only include the tags whose title/description is blank. The natural question follows: why does Yoast WordPress SEO want to exclude tags with custom SEO title and/or description from the sitemap? Perhaps the values of these fields must conform to a certain standard or format? If that’s the case, what are the guidelines? (number of characters, prohibited characters, etc.)
