select power, and turn it off. Then turn it back on!
The other my cowarkers worked hard on inputting about 20 minutes of stuff into an application, and saved it. They then went back to it a couple of minutes later, and started typing again, only to remove all of the items that they already had inputted. They started freaking out. I told them to close the application and DONT SAVE CHANGES!
They got back into the application without issues, and the original stuff was still there.
Computing is not complicated, we make it that way!