Mail Calendar and People app disappears from my Surface RT

[James Orenberg]

Since a Windows upgrade in May, my Mail, Calendar and People app disappears on my Surface RT. When I install it via the Store, it installs, but I cannot find it. I have tried installing half a dozen times, but without success. A notification that storage space is limited comes up from time to time, but I have added nothing to the file structure in many months. Any ideas on this disappearing app?