I'm getting a parsing error in my /post-sitemap.xml file in Webmaster Tools.
The error description reads: We were unable to read your Sitemap. It may contain an entry we are unable to recognize. Please validate your Sitemap before resubmitting.
It identifies the offending line number, but I can't work out how to open the sitemap to see what that line refers to (it won't open in a browser).
I've tried turning off and on the sitemap function and deactivated and activated the plugin.