I went to Google Webmaster Tools to insure I had my sitemap.xml listed in the correct location (it wasn't, so I updated the location)
The sitemap.xml is viewable in a web browser no problem, and Google has accepted it's updated location.
But Google has rejected the sitemap.xml.gz stating:
Unsupported file format
Your Sitemap does not appear to be in a supported format. Please ensure it meets our Sitemap guidelines and resubmit.
To check it out , I used IE, pointed my browser at http://www.example.com/sitemap.xml.gz and downloaded the file to my computer (for some reason I couldn't get windows to recognize and unzip the gzip), so I then uploaded it back to my server and unzipped it.
Tried to access the file location via a browser and got this error message:
Error loading stylesheet: An unknown error has occurred (805303f4)http://www.example.com/wp-content/plugins/wordpress-seo/css/xml-sitemap.xsl
When I open the doc to edit it, the header reads like this:
<?xml version="1.0" encoding="UTF-8"?><?xml-stylesheet type="text/xsl" href="http://www.example.com/wp-content/plugins/wordpress-seo/css/xml-sitemap.xsl"?>
<urlset xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.sitemaps.org/schemas/sitemap/0.9 http://www.sitemaps.org/schemas/sitemap/0.9/sitemap.xsd" xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">