After updating to WP 3.7 I got the dreaded blank white screen when viewing my website.
Here are the steps I took to get it working again:
1.DEACTIVATE the Timely Event calendar plugin (your site should now be visible after refreshing your browser)
2.** IMPORTANT*** Follow these instructions to remove the file delete script for the plugin otherwise you will lose ALL your events!: http://support.time.ly/manually-upgrading-the-calendar/
3.DELETE the Timely Event calendar plugin. THE DELETE FILES MESSAGE WILL STILL BE DISPLAYED BUT YOUR EVENT DATA WILL NOT BE DELETED.
4.REINSTALL the latest Timely Event calendar plugin
5.REACTIVATE the Timely Event calendar plugin
6.Your site should now be visible and the Timely Event calendar plugin should work correctly.
You will probably get a notice that there is an updated version:
You have version 1.10.1-standard installed. Update to 1.10.3.
DO NOT UPDATE OR YOU WILL BE BACK TO A BLANK