Sitemap was ok when I use WP 3.7. After I upgraded WP to 3.7.1, I thought everything was ok. However, when I checked sitemap on http://localhost/mysite/sitemap_index.xml, I got warning:
XML Parsing Error: XML or text declaration not at start of entity
Line Number 2, Column 1:<?xml version="1.0" encoding="UTF-8"?><?xml-stylesheet type="text/xsl" href="http://localhost/mysite/main-sitemap.xsl"?>
What is wrong? Any thoughts on it?