It's been about two weeks since upgrading to the Windows 8.1 Preview, and I haven't gotten a single toast from an app. There have been many restarts, and everything is up to date as far as Windows Update and the Store are concerned.
I used to get toasts from email, calendar, messaging, Skype, Xbox Live, etc. but I never get anything now, and I'm not sure how to troubleshoot.
I've tested email by making sure the program was running in the background and sending myself an email from a different address via webmail. I was never notified.
How can I troubleshoot this?