Ever since I changed my forum software from bbpress to punbb I haven’t got any of the pages indexed by google. Not even the home page. Indeed G-Webmasters Tools reported some errors.

As the detail report told me that it was probably caused by the failure attempt of google bot to reach my server, so that I thought this sitemap problem would be fixed by itself in a day or two and subsequently I took no action.

But look what I get: it persists