diff --git a/tst/memfs/memfs-main.c b/tst/memfs/memfs-main.c
index b6ddf019..8d1c1b81 100644
--- a/tst/memfs/memfs-main.c
+++ b/tst/memfs/memfs-main.c
@@ -90,7 +90,8 @@ NTSTATUS SvcStart(FSP_SERVICE *Service, ULONG argc, PWSTR *argv)
         goto exit;
     }
 
-    Result = FspFileSystemSetMountPoint(MemfsFileSystem(Memfs), MountPoint);
+    Result = FspFileSystemSetMountPoint(MemfsFileSystem(Memfs),
+        MountPoint && MountPoint[0] ? MountPoint : 0);
     if (!NT_SUCCESS(Result))
     {
         fail(L"cannot mount MEMFS");