diff --git a/module/os/windows/zfs/zfs_vnops_windows.c b/module/os/windows/zfs/zfs_vnops_windows.c
index 349dfa1a844c..5eb06b2da664 100644
--- a/module/os/windows/zfs/zfs_vnops_windows.c
+++ b/module/os/windows/zfs/zfs_vnops_windows.c
@@ -132,6 +132,16 @@ zfs_AcquireForLazyWrite(void *Context, BOOLEAN Wait)
 	struct vnode *vp = fo->FsContext;
 	dprintf("%s:fo %p\n", __func__, fo);
 
+	if (unlikely((zmo->vpb->Flags & VPB_MOUNTED) == 0)) {
+		dprintf("%s: fo %p not mounted\n", __func__, fo);
+		return (FALSE);
+	}
+
+	if (unlikely(zfsvfs == NULL)) {
+		dprintf("%s: fo %p already freed zfsvfs\n", __func__, fo);
+		return (FALSE);
+	}
+
 	/* Confirm we are mounted, and stop unmounting */
 	if (vfs_busy(zfsvfs->z_vfs, 0) != 0)
 		return (FALSE);
diff --git a/module/os/windows/zfs/zfs_vnops_windows_mount.c b/module/os/windows/zfs/zfs_vnops_windows_mount.c
index 4673a8fbfedf..1aabdbf87a04 100644
--- a/module/os/windows/zfs/zfs_vnops_windows_mount.c
+++ b/module/os/windows/zfs/zfs_vnops_windows_mount.c
@@ -1583,6 +1583,12 @@ zfs_windows_unmount(zfs_cmd_t *zc)
 		if (error)
 			goto out_unlock;
 
+		if (zmo_dcb != NULL) {
+			// zfs_vfs_unmount already freed the zfsvfs, but
+			// a reference still exists in the DCB.
+			vfs_setfsprivate(zmo_dcb, NULL);
+		}
+
 		// Release devices
 		IoDeleteSymbolicLink(&zmo->symlink_name);