Okay so I can tell you that definitely works! Thank you very much. I created a list.txt, put in the path to my .xci and ran the NSCB.bat in manual mode. Finally the program found my .xci and converted it to .nsp without a problem.
I'm afraid that didn't help. I don't have any spaces in my path so that's not my problem. In the picture I added to this post you can see the cmd output. This was for the "automatic" way by dragging my .xci onto the NSCB.bat. Manual mode is pretty much the same. Dragging the file onto the window...
No idea what I'm doing wrong. I always get "File not found" error message. I tried different folders for the xci file and the program, even put it on C:\, I tried different PCs, I tried different Python versions and renaming files. Always get a "File not found" error message while trying to...