A Databricks ADLS mount 403 is auth, network or ACL—not a bad path. Read the HEAD/getAccessControl text, then fix RBAC, firewall or POSIX ACLs, or move to a Unity Catalog external location.
Fix [PATH_NOT_FOUND] Path does not exist errors when a Databricks notebook reads ADLS Gen2: what the error means, how to find the first wrong path segment, and fixes for abfss URIs, globs, late files, mounts and Unity Catalog volumes.