diff --git a/sdk/lib/rtl/srw.c b/sdk/lib/rtl/srw.c
index 8b5b47ce59f..68ac2614786 100644
--- a/sdk/lib/rtl/srw.c
+++ b/sdk/lib/rtl/srw.c
@@ -791,5 +791,5 @@ BOOLEAN
 NTAPI
 RtlTryAcquireSRWLockExclusive(PRTL_SRWLOCK SRWLock)
 {
-    return InterlockedCompareExchangePointer(&SRWLock->Ptr, (ULONG_PTR*)(ULONG_PTR)RTL_SRWLOCK_SHARED, 0) == 0;
+    return InterlockedCompareExchangePointer(&SRWLock->Ptr, (ULONG_PTR*)RTL_SRWLOCK_OWNED, 0) == 0;
 }