The "Create html site map for your visitors" was unchecked, so I don't have a sitemap.html file.
If I enable it, the error stays the same.
It was unchecked, but a path to the sitemap was there.
If I remove the path to the sitemap, and uncheck it again, I get
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An error occured
Sitemap file is not writable:
Sitemap file is not writable:
Sitemap file is not writable:
Sitemap file is not writable:
Sitemap file is not writable:
Sitemap file is not writable:
Sitemap file is not writable:
Sitemap file is not writable:
Sitemap file is not writable:
Sitemap file is not writable:
Sitemap file is not writable:
Sitemap file is not writable:
Sitemap file is not writable:
Sitemap file is not writable: