I know there were similar problems like this but each and every problem is different.
recently move my site to new server.
After that i am getting
magento customer grid.
Uncaught TypeError: Cannot call method 'select' of null and accordian is also not loading properly.
I get this error
after i click on each customer.
May be for this reason
i am getting 500 internal server error on that page.
Memory limit is given in .htaccess in 512MB & permission is given 777 to all js->mage->adminhtml