Unable to access files using a classic cluster

NW1000
New Contributor III

I used the same code with the classic cluster (RunTime 17.3LTS ML, with spark config: "spark.databricks.workspace.fileSystem.enabled true"), not able to access files in workspace with the following python code

import os
# Check if source exists and what's in it
src = "/Workspace/Users/xxx@xxxxxx.com/reporting/R/utils"
print(f"Source exists: {os.path.exists(src)}")
print(f"Source contents: {os.listdir(src) if os.path.exists(src) else 'N/A'}")
Result:
Source exists: True
Source contents: []
However, using serverless compute, the result is:
Source exists: True
Source contents: ['aaa_helpers.R', 'write_metadata.R', 's3_helpers.R', '.gitkeep']
Therefore, the files can be accessed using the python code, but not able to be accessed using the classic cluster. Could anyone point out why? Thanks a lot.