Error when entering theme settings

I am working with a new theme and now when I try to enter the Theme section under Settings I get the following error:

404: Page Not Found

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I have tried replacing the config.ini file to no avail and don't know what I could have changed to cause the problem.

What's the URL that's giving you this error?

And this happened only because you added a new theme? Have you tried removing (or just moving) the theme?

Follow the "Display Error Messages" instructions from the documentation. That should get you a message giving some more detail about why you're getting that 404 error there.

This is the error I get after removing my theme and restoring the themes folder to what is provided with 1.5.3

script 'page/show.php' not found in path (/home/bgcdml/

#0 /home/bgcdml/ Zend_View_Abstract->_script('page/show.php')
#1 /home/bgcdml/ Zend_View_Abstract->render('page/show.php')
#2 /home/bgcdml/ Zend_Controller_Action_Helper_ViewRenderer->renderScript('page/show.php', NULL)
#3 /home/bgcdml/ Zend_Controller_Action_Helper_ViewRenderer->render()
#4 /home/bgcdml/ Zend_Controller_Action_Helper_ViewRenderer->postDispatch()
#5 /home/bgcdml/ Zend_Controller_Action_HelperBroker->notifyPostDispatch()
#6 /home/bgcdml/ Zend_Controller_Action->dispatch('showAction')
#7 /home/bgcdml/ Zend_Controller_Dispatcher_Standard->dispatch(Object(Zend_Controller_Request_Http), Object(Zend_Controller_Response_Http))
#8 /home/bgcdml/ Zend_Controller_Front->dispatch()
#9 /home/bgcdml/ Zend_Application_Bootstrap_Bootstrap->run()
#10 /home/bgcdml/ Zend_Application->run()
#11 /home/bgcdml/ Omeka_Core->run()
#12 {main}

I'm not sure this is related to the theme.

Did you recently create a simple page with the name 'themes'? This looks like it's trying to show a Simple Page on the admin side of the site, which won't work.

Upgrading to Simple Pages 1.3.1 should prevent these kinds of conflicts between page names and admin URLs?

Thanks, that was the problem, had a page called themes. Changed the slug to thematic-essays and it fixed it.