RH11 - Information in TOC was lost not just for one but for all of RH project files

I have a client who accidentally clicked on the X in one of her TOC pods on one project. Unfortunately, it appears that she has lost all of the contents in the Table of Contents and is now having to rebuild it. There is no reason that I can think of that would empty the contents of the TOC as it had previously been saved. Even if she had made a few changes to it, the entire TOC should not have been lost in my view. The TOC file exists but there is nothing in it.

Then she opened her other RoboHelp projects and discovered that the TOC for each of her RH projects was also lost. Can anyone tell me how this could happen? I have never encountered this before so I am not sure how this should be avoided.

She was in the process of moving her pods around on the screen and rather then pinning it in place she hit the x. By the time she showed me her file all of the project pods were no longer displaying. I showed her how to add them back in to her view but the situation with the TOC is a complete mystery. Any help anyone can give me would really be appreciated.