We are running Umbraco version 7.1.8 assembly: 1.0.5394.16131. Our sit eis hosted by Godaddy using Deluxe Windows Hosting with Plex. A few weeks ago our site was throwing an error. I wish I had written it down because I don't remember the details. What I do remember is that the fix, as suggested by a post here, was to restore the trees.config file. The symptoms pointed to the file being suddenly empty. It was, so I restored it from a backup and the site came back up.

Now, when we try to make changes to the site the admin navigation on the left site of the back end is missing. Strangely, the one way to bring it back it to bring up the trees.config file in the Godaddy online editor and save it -- with no changes. This brings the admin menu back, but only temporarily. We aren't sure how long it lasts, but when we come back to make more changes the admin nav has disappeared again.

I can't find anything even close to a solution for this problem. Any help would be greatly appreciated.