Failed to load maps when transferring to a new PC

I am trying to move my project from one PC to a second PC. I copied the entire project folder (without zipping) to the same location on the second PC. The project opened, but when I tried to open the level I was working on, I got the following error:

I was unable to find the missing file on either PC. Any help is greatly appreciated!

Shouldn’t be a problem. Just rebuild light if you are not using dynamic lights and save the project.

I decided to start over with a new file since I was spending more time trying to solve the problem than it was going to take to re-create the project. I will definitely try this if the same problem pops up again! Thanks!!