diff --git a/ntoskrnl/io/iomgr/volume.c b/ntoskrnl/io/iomgr/volume.c
index 1d1e31e5c0..80b2d6835f 100644
--- a/ntoskrnl/io/iomgr/volume.c
+++ b/ntoskrnl/io/iomgr/volume.c
@@ -129,6 +129,14 @@ IopCheckVpbMounted(IN POPEN_PACKET OpenPacket,
          */
         else if (Vpb != NULL)
         {
+            if (Vpb->Flags & VPB_LOCKED)
+            {
+                /* We're locked, so fail */
+                *Status = STATUS_ACCESS_DENIED;
+                return NULL;
+            }
+
+            Vpb->ReferenceCount++;
             return Vpb;
         }