White screen after deleting a module
If you deleted and returned a module to its original place, then all it takes for the website to start working normally again is to get cache refreshed, which will bootstrap it.

You can do it by:


Running the update.php file. Make sure to set $settings['update_free_access'] = TRUE; on the settings.php file.
Using drush. Installing drush is not as complicated as it might sound. Just follow instructions on http://docs.drush.org/en/master/install.
By clearing cache tables directly in the database. Just use some kind of user interface for the database like, for example, phpMyAdmin, open the website's database and truncate all the tables starting with cache.
If none of the above methods works, then try to uninstall and re-install the module or manually remove all database references to the fields which were created by the module.