Run a disk check:
Resolving an "Access Denied" error requires a methodical approach. The following steps are ordered from the least intrusive to the most advanced.
Always connect the problematic drive as an internal drive or via USB. For system drives (C:), boot from a recovery USB.
The process detailed in Phase II (Taking Ownership) is the standard fix. However, for large drives, changing permissions on millions of files can take hours. Users are advised to perform this at the root of the drive to ensure comprehensive access restoration.