Some things to try (in the order given because step (2) may overwrite the history used in step (1 and step (3) may delete the history)):
1. Try looking through the Crash Recovery history to see if it looks like you have accidentally deleted the project containing the files:
![Crash Recovery][1]
2. Try refreshing the browser window (the F5 key);
3. Logout, close the window, reopen it and log in again.
[1]: /editor/20150909/55f00d5b5519f.png
Please, where in the interface is the button to delete a document ? If I delete it from the history window, it will still be present in the project after signing out and in again, although with no previous versions anymore.
Alhtough I deleted the document (it is not in the dropdown list in the editor anymore), it is still visible in the page "Home > My Account > My project's Docs" and accessible and editable.
Our website uses essential cookies to help us ensure that it is working as expected, and uses optional analytics cookies to offer you a better browsing experience. To find out more, read our Cookie Notice
Brand new interactions and interfaces. 
Easy to use and quick to get started. 