Disable mod_pagespeed (no server conf access, .htaccess doesn't work)

Create a .htaccess file, add below text and upload using ftp program. We are also a hosting provider and use Pagespeed.

Modpagespeed Off

Your URL can accept the PageSpeed query-paramter with an off or on value.

http://www.example.com/index.html?PageSpeed=off

or

http://www.example.com/index.html?q=foo&PageSpeed=off

more here.

Which hosting provider? Can you make sure your server is Apache rather than nginx? nginx doesn't support .htaccess files, though the PageSpeed module is otherwise very similar in function.

Also check out the 'pedantic' filter: https://developers.google.com/speed/pagespeed/module/filter-pedantic, which let's you get all the speed & bandwidth benefits of PageSpeed but still have a validation-clean site.