HTTPS and SecurePages Infinite Redirect - How do I reset which pages are always HTTPS?
I pulled this directly from the README.txt of the module.


  Configuration
  
  Generally on test/development servers you do not have access to SSL,
  so  generally you would like to disable secure pages on these systems.
  
  To do this add the following to your settings.php
  
  $conf['securepages_enable'] = 0;
  
  Removal of SecurePages
  
  In the case where your SSL mode has been disabled and you can no
  longer access the administration section of your site to disable
  securepages you can do one of the 2 following things.
  
  
  Use the above method to disable securepages.
  delete the secure pages module from your site.
  
  
  If you can use the first option but if you can't edit your
  settings.php then deleting it will not break your site, but will leave
  some variables that are set by secure pages.