diff --git a/core/libs/prx/libc/src/FileLock.cpp b/core/libs/prx/libc/src/FileLock.cpp
index 1ed227981..40efecd96 100644
--- a/core/libs/prx/libc/src/FileLock.cpp
+++ b/core/libs/prx/libc/src/FileLock.cpp
@@ -15,6 +15,8 @@ constexpr int LockShared = 1;
 constexpr int LockExclusive = 2;
 constexpr int LockNonblocking = 4;
 constexpr int LockUnlock = 8;
+constexpr DWORD LockByteLow = 0xFFFFFFFE;
+constexpr DWORD LockByteHigh = 0x7FFFFFFF;
 
 struct LockState {
     std::mutex mutex;
@@ -55,14 +57,18 @@ int GuestFileLock_nid_no_patch(int fd, int operation) {
     if (state->mode == mode) return 0;
     if (state->mode != 0) {
         OVERLAPPED overlapped{};
-        if (!::UnlockFileEx(handle, 0, MAXDWORD, MAXDWORD, &overlapped)) return -1;
+        overlapped.Offset = LockByteLow;
+        overlapped.OffsetHigh = LockByteHigh;
+        if (!::UnlockFileEx(handle, 0, 1, 0, &overlapped)) return -1;
         state->mode = 0;
     }
     if (mode == LockUnlock) return 0;
     DWORD flags = mode == LockExclusive ? LOCKFILE_EXCLUSIVE_LOCK : 0;
     if (operation & LockNonblocking) flags |= LOCKFILE_FAIL_IMMEDIATELY;
     OVERLAPPED overlapped{};
-    if (!::LockFileEx(handle, flags, 0, MAXDWORD, MAXDWORD, &overlapped)) return -1;
+    overlapped.Offset = LockByteLow;
+    overlapped.OffsetHigh = LockByteHigh;
+    if (!::LockFileEx(handle, flags, 0, 1, 0, &overlapped)) return -1;
     state->mode = mode;
     return 0;
 }