Worked fine testing it against my local temp directory. However when trying to run it against a bigger folder tree, which contains directories, where the current user does not have access to, it fails.

C:\Users\ggruber.WORKFLOW\Documents\GitHub\coding-challenges-mateen\folder-analyzer>node analyser.js c:\users\ggruber.workflow
fs.js:961
binding.lstat(pathModule.toNamespacedPath(path));
^

Error: EPERM: operation not permitted, lstat 'c:\users\ggruber.workflow\AppData\Local\ElevatedDiagnostics'
at Object.fs.lstatSync (fs.js:961:11)
at files.forEach (C:\Users\ggruber.WORKFLOW\Documents\GitHub\coding-challenges-mateen\folder-analyzer\analyser.js:112:25)
at Array.forEach ()
at analyzingDir (C:\Users\ggruber.WORKFLOW\Documents\GitHub\coding-challenges-mateen\folder-analyzer\analyser.js:110:11)
at files.forEach (C:\Users\ggruber.WORKFLOW\Documents\GitHub\coding-challenges-mateen\folder-analyzer\analyser.js:119:13)
at Array.forEach ()
at analyzingDir (C:\Users\ggruber.WORKFLOW\Documents\GitHub\coding-challenges-mateen\folder-analyzer\analyser.js:110:11)
at files.forEach (C:\Users\ggruber.WORKFLOW\Documents\GitHub\coding-challenges-mateen\folder-analyzer\analyser.js:119:13)
at Array.forEach ()
at analyzingDir (C:\Users\ggruber.WORKFLOW\Documents\GitHub\coding-challenges-mateen\folder-analyzer\analyser.js:110:11)

Is it possible to fix, that?

This was due to user's permission to directory structure, I have fixed this issue in latest commit "mateenmohsin@9435b12"

Could you improve your fix, that the directory, which is not accessible is just skipped and the process of analyzing will just continue with the rest of the directory tree?
Goal should be to get a result for those parts of the folder hiearchy, which are accessible.

Improved the fix in latest commit : 9ce436d