Admin Module frontpage has gone - How do I get it back? I took the liberty to upgrade to v7.25 today; four hours later (after trying to get back to where I was 8 hours before) I had to used Backup and Migrate to restore my previous v7.24. I've tried numerous update.php attempts but my Admin Module page just will not show via /admin/modules path. I can get admin/uninstall but any attempt to get back to /admin/modules gives me a black white screen so I cannot manage any modules.

Can anyone suggest a solution. I'm aware of Drush and have it to hand, but not too aufait at present (I'm on an Ubuntu desktop with localhost). 

I do get a PDO error starting as:
PDOException: SQLSTATE[42S22]: Column not found: 1054 Unknown column 'has_children' in 'field list':......

if that has any influence.

Thanks.
Try using phpMyAdmin. Backup again, then show the system table. Change the status of the problem module from 1 to  0 from phpMyAdmin. Then refresh Drupal pages to see if it resolves it. Other modules might be the issue so try process of eleimaination, toggling 1 to 0. If the 0 works, try and uninstall then reinstall if practical.