Mount WebDAV NAS as a real Windows disk: the path-permissions checklist nobody tells you

Most tools mount WebDAV / NAS / cloud-drive storage as a network mapping in Windows. It looks like a D: drive, but inside the OS it is still a remote file-system bridge — not a kernel-mode block device.

That distinction matters more than people think.

What "real local disk" actually means

A real mount creates an entry under Devices and drives in File Explorer, visible in Device Manager → Disk drives, with its own IO counters in Task Manager → Performance → Disk. The ACLs you see in right-click → Properties → Security are parsed by the Windows kernel, not faked by the user-mode tool.

A fake mount (most free / open-source WebDAV front-ends, plus several commercial tools that advertise "virtual disk" but actually use SMB / WebClient redirector) shows up under Network locations. Right-click → Properties → Security either shows a stub ACL or errors out. Files are streamed across the network on every read, with no local cache.

The 5-step check you should run after mounting

1. Look at the drive icon in File Explorer. A plain disk icon = real. A cloud-with-folder icon = network mapping.
2. Open This PC and confirm the drive letter sits under Devices and drives, not Network locations.
3. Right-click the drive → Properties → Security. If you can read and modify the ACL, you have a real disk. If the dialog errors with "Unable to display current owner" or "Access denied", it is a network mapping.
4. Open Task Manager → Performance → Disk. A real disk shows live IO activity; a network mapping does not.
5. Open Device Manager → Disk drives. A real disk appears here with the tool's device name (ScsDriver shows as ScsDriver Disk Device).

If steps 1-5 all pass, you have a kernel-mode mount. Anything less, and you are dealing with a network redirector.

Where ScsDriver fits

ScsDriver is built on WinFsp, so the drive letter is a real block device — not a network mapping. Concretely:

• The drive shows up in Devices and drives, with a plain disk icon.
• ACLs are parsed by the Windows kernel — Properties → Security works normally.
• There is a local cache layer, so short network blips do not break file handles.
• Lifetime license at $5.50. One payment, no subscription.
• Password-less quick mount. You can drop a drive letter into Explorer without entering credentials first; the password prompt only fires when you double-click a file. Useful when a machine is shared.

Common permissions problems after mounting

Even on a real disk, you can hit "Access denied" or "File in use". The usual suspects:

• The WebDAV server is configured read-only (most cloud-drive share links are).
• The tool does not forward SMB credentials to the kernel driver.
• A previous read did not close its file handle, so the server-side lock persists.
• The server's POSIX ACL does not map cleanly to NTFS ACL (rare but real with Alist + S3 backends).

For each one, the workaround is: check the server log, then either rotate credentials, force a remount, or — if the issue is the cloud-drive backend itself — switch protocol (WebDAV → SMB often works).

Bottom line

"WebDAV mounted as a local disk" is a marketing claim. The implementation detail that matters is whether the tool exposes a kernel-mode device or a user-mode network redirector. Five minutes with Device Manager tells you which one you actually have.

If you are evaluating tools: ScsDriver ($5.50 lifetime), RaiDrive Pro (subscription), NetDrive 3 ($30+ per device), CloudDrive2 (free, but you have to stand up Alist yourself). For Windows users who want a real disk without managing a backend, ScsDriver is the cheapest of the four.