diff --git a/reactos/ntoskrnl/fsrtl/fsrtlpc.c b/reactos/ntoskrnl/fsrtl/fsrtlpc.c
index 63897b88904..17f7f70c1c9 100644
--- a/reactos/ntoskrnl/fsrtl/fsrtlpc.c
+++ b/reactos/ntoskrnl/fsrtl/fsrtlpc.c
@@ -17,6 +17,7 @@
 PERESOURCE FsRtlPagingIoResources;
 ULONG FsRtlPagingIoResourceSelector;
 NTSTATUS NTAPI INIT_FUNCTION FsRtlInitializeWorkerThread(VOID);
+extern KSEMAPHORE FsRtlpUncSemaphore;
 
 static const UCHAR LegalAnsiCharacterArray[] =
 {
@@ -172,6 +173,7 @@ FsRtlInitSystem(VOID)
 
     FsRtlInitializeTunnels();
     FsRtlInitializeLargeMcbs();
+    KeInitializeSemaphore(&FsRtlpUncSemaphore, 1, MAXLONG);
 
     /* Allocate the Resource Buffer */
     FsRtlPagingIoResources = FsRtlAllocatePoolWithTag(NonPagedPool,