Jupyter Recognizes file path in one script but not other

Beginner here.

I worked with a file two days ago using the path:

file=open(‘Desktop/LL/Ex/Data/ciRF_VSL2_2.csv’)

I tried to create a new notebook, and it couldn’t find any of my files. So I opened the old one today, still runs fine. Tried pasting the same line in the new notebook and it can’t find it. Tried duplicating the original notebook so I could temporarily work around this - doesn’t give me the option any more. Am I running Jupyter on a different server or something? It shows all the right files from my computer in their expected spots.

Did you try running pwd in a cell in both the new notebook and the old one? Is the current working directory the same? (See here about pwd if you are unfamiliar.)

You don’t say what type of system you are running on?
Normally, on Mac or Linux, you’d probably want that path prefaced by ~/ to make it an absolute path instead of relative, see here. Specifically with your example, you’d have more reproducibility with:

file=open(‘~/Desktop/LL/Ex/Data/ciRF_VSL2_2.csv’)