Are you using Photoshop Elements or Premiere Elements?
Are you trying to save a project or file over itself? Do you run into the same problem if you rename your file?
What program are you using - Photoshop Elements 13 or Premiere Elements 13. I. By the nature of your question, I suspect Photoshop Elements 13. If this is the case, then you have posted in the wrong forum. Some how your thread go posted in the Adobe Premiere Elements Forum (video editing).
If your program is Photoshop Elements 13, please re-post your thread in the Adobe Photoshop Elements Forum.
with more details.
If Premiere Elements is your program, please give more details in this thread, and I will customize a reply based on the details in your reply.