diff --git a/db/db_test.cc b/db/db_test.cc
index 2fb6226f2..e0f3996be 100644
--- a/db/db_test.cc
+++ b/db/db_test.cc
@@ -8725,6 +8725,15 @@ class RecoveryTestHelper {
         test->dbname_ + "/" + wal_files.front()->PathName();
     auto size = wal_files.front()->SizeFileBytes();
 
+#ifdef OS_WIN
+    // Windows disk cache behaves differently. When we truncate
+    // the original content is still in the cache due to the original
+    // handle is still open. Generally, in Windows, one prohibits
+    // shared access to files and it is not needed for WAL but we allow
+    // it to induce corruption at various tests.
+    test->Close();
+#endif
+
     if (trunc) {
       ASSERT_EQ(0, truncate(logfile_path.c_str(), size * off));
     } else {
diff --git a/port/win/env_win.cc b/port/win/env_win.cc
index 27c5c3fbd..d29a63a6e 100644
--- a/port/win/env_win.cc
+++ b/port/win/env_win.cc
@@ -2405,7 +2405,7 @@ public:
         queue_.push_back(BGItem());
         queue_.back().function = function;
         queue_.back().arg = arg;
-        queue_.back().arg = tag;
+        queue_.back().tag = tag;
         queue_len_.store(queue_.size(), std::memory_order_relaxed);
 
         if (!HasExcessiveThread()) {
diff --git a/port/win/port_win.cc b/port/win/port_win.cc
index 7e0b45cfd..0ea706c79 100644
--- a/port/win/port_win.cc
+++ b/port/win/port_win.cc
@@ -215,7 +215,7 @@ int truncate(const char* path, int64_t len) {
 
   HANDLE hFile = CreateFile(path,
     GENERIC_READ | GENERIC_WRITE,
-    0, // No sharing while truncating
+    FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE,
     NULL, // Security attrs
     OPEN_EXISTING, // Truncate existing file only
     FILE_ATTRIBUTE_NORMAL,