If you want to move a project you need to move the source / target files as well - basically keep the structure of the folders intact.
Alternatively you can change the paths of the files in the project:
https://docs.sdl.com/LiveContent/content/en-US/SDL%20Passolo%20Help-v2/GUID-5200C248-6DEA-41C7-A230-525F1E419DEB