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+Windows has no FUSE of its own, so `weed mount` goes through [WinFsp](https://winfsp.dev/), which provides the filesystem driver. The filesystem code underneath is the same one Linux and macOS run, so behaviour matches those platforms except where Windows cannot express something.
+
+This is beta. It is exercised by CI on every change, but it has had far less production use than the unix mount.
+
+### Install WinFsp
+
+Download the installer from [winfsp.dev](https://winfsp.dev/rel/) or:
+
+```powershell
+choco install winfsp
+```
+
+The default feature set is enough. `weed.exe` loads `winfsp-x64.dll` at run time, so nothing is needed at build time and no developer package is required. WinFsp supports x86, x64 and ARM64; the architecture has to match the `weed.exe` you run.
+
+### Mount
+
+```powershell
+weed.exe mount -filer=127.0.0.1:8888 -dir=S:
+```
+
+The mount point is one of:
+
+* a **drive letter**, `S:`, which must be free
+* a **directory that does not exist yet**, `C:\seaweed\data` — its parent must exist, and WinFsp creates it
+* a **UNC path**, `\\seaweedfs\data`
+
+An existing directory is rejected: WinFsp cannot mount over one.
+
+Prefer `127.0.0.1` over `localhost`. Windows resolves `localhost` to `::1` first, and a filer listening only on IPv4 will refuse the connection.
+
+Stop the mount with Ctrl-C, which unmounts cleanly and flushes pending writes. Killing the process leaves anything not yet flushed unwritten, the same as pulling the plug on any filesystem.
+
+### Windows-specific options
+
+| Flag | Meaning |
+| --- | --- |
+| `-windows.caseInsensitive` | Match names case-insensitively. Off by default. |
+| `-readOnly` | Reject every modification at the WinFsp layer. |
+| `-cacheMetaTtlSec` | How long WinFsp may cache attributes and directory entries. |
+| `-debug.fuse` | Log every filesystem operation. |
+
+Everything else — `-cacheDirForRead`, `-cacheSizeMBForRead`, `-chunkSizeLimitMB`, `-collection`, `-replication`, `-concurrentWriters` — behaves as it does elsewhere. See [[FUSE Mount]].
+
+#### Case sensitivity
+
+The filer is case-sensitive, and so is the mount by default: `Report.txt` and `report.txt` are two files. Some Windows software assumes otherwise and will misbehave. `-windows.caseInsensitive` makes the mount match Windows expectations, at the cost of making one of any two names that differ only in case unreachable. WinFsp cannot do NTFS-style mixed sensitivity, so it is one or the other for the whole mount.
+
+#### Coherence between mounts
+
+There is no way to invalidate the Windows cache from the filesystem side, so a mount notices another mount's changes only once its cached attributes expire. Lower `-cacheMetaTtlSec` if several machines write the same files; raise it if a single machine wants the metadata cache to work harder.
+
+### Large directories
+
+A directory with hundreds of thousands of entries enumerates fine — the mount pages through it rather than materialising the whole listing, and CI covers directories in the thousands. Explorer itself is the slow part at that size; `dir`, PowerShell and application code are much faster than the graphical shell.
+
+### What Windows cannot do
+
+| | |
+| --- | --- |
+| Hard links | Not supported by WinFsp. `mklink /H` fails. |
+| Symbolic links | Refused. The entry would need a reparse point the mount does not create yet. |
+| Byte-range locks | Handled inside the WinFsp driver, so they are local to one machine. The mount's distributed locking does not extend to Windows. |
+| Extended attributes | Not wired up. |
+| POSIX ownership | Files belong to whoever started the mount. Unix uid/gid do not map onto Windows accounts. |
+
+Entries whose names Windows cannot represent are invisible from a Windows mount, and stay reachable from other clients. That means anything containing `\ / : * ? " < > |`, anything ending in a space or a dot, and the reserved device names `CON`, `PRN`, `AUX`, `NUL`, `COM1`-`COM9`, `LPT1`-`LPT9`.
+
+### Running as a service
+
+`weed mount` runs in the foreground and a mount belongs to the session that created it, so a mount started by hand disappears at logout and is not visible to services. To keep one up, run it as a Windows service with a wrapper such as [WinSW](https://github.com/winsw/winsw) or [NSSM](https://nssm.cc/), and give WinFsp `-o UNC` or a drive letter that the service account can reach.
+
+### Troubleshooting
+
+**"WinFsp refused to mount S:"** — WinFsp is not installed, the drive letter is taken, or the mount point already exists. `net use` lists the drive letters in use.
+
+**The mount exits reporting it cannot reach the filer** — check the filer's gRPC port, which is its HTTP port plus 10000 (`8888` → `18888`). It is the gRPC port the mount dials, so a filer answering on HTTP is not proof it is reachable. Use `127.0.0.1` rather than `localhost`.
+
+**Nothing appears in the logs** — `weed.exe` writes through glog, which logs to its own files by default. Pass `-logtostderr` *before* the subcommand, since glog's flags are global:
+
+```powershell
+weed.exe -logtostderr mount -filer=127.0.0.1:8888 -dir=S:
+```
+
+**Explorer is sluggish in a huge directory** — it is rendering, not the filesystem. Compare against `dir` in the same folder before investigating further.
+
+### Building from source
+
+```powershell
+$env:CGO_ENABLED=0
+go build -o weed.exe ./weed
+```
+
+`CGO_ENABLED=0` matters. With cgo enabled the FUSE binding compiles against WinFsp's C headers, which the default install does not ship; without it the binding loads the DLL at run time instead. This is also how the released `weed.exe` is built, and it means Windows builds cross-compile from Linux or macOS:
+
+```bash
+CGO_ENABLED=0 GOOS=windows GOARCH=amd64 go build -o weed.exe ./weed
+```
diff --git a/_Sidebar.md b/_Sidebar.md
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--- a/_Sidebar.md
+++ b/_Sidebar.md
@@ -60,6 +60,7 @@
 * [[Filer Operation Serialization]]
 
 ### [[FUSE Mount]]
+* [[Mount on Windows]]
 * [[FIO benchmark]]
 * [[fstab and systemd mount]]
 * [[POSIX Compliance]]