diff --git a/other-licenses/nsis/Contrib/InetBgDL/InetBgDL.cpp b/other-licenses/nsis/Contrib/InetBgDL/InetBgDL.cpp
index cbebe1b4b92..8b7a5d760a5 100644
--- a/other-licenses/nsis/Contrib/InetBgDL/InetBgDL.cpp
+++ b/other-licenses/nsis/Contrib/InetBgDL/InetBgDL.cpp
@@ -20,6 +20,7 @@ typedef DWORD FILESIZE_T; // Limit to 4GB for now...
 HINSTANCE g_hInst;
 NSIS::stack_t*g_pLocations = NULL;
 HANDLE g_hThread = NULL;
+HANDLE g_hGETStartedEvent = NULL;
 volatile UINT g_FilesTotal = 0;
 volatile UINT g_FilesCompleted = 0;
 volatile UINT g_Status = STATUS_INITIAL;
@@ -71,6 +72,14 @@ NSIS::stack_t* StackPopItem(NSIS::stack_t**ppST)
 
 void Reset()
 {
+  // The g_hGETStartedEvent event is used to make sure that the Get() call will
+  // acquire the lock before the Reset() call acquires the lock.
+  if (g_hGETStartedEvent) {
+    WaitForSingleObject(g_hGETStartedEvent, INFINITE);
+    CloseHandle(g_hGETStartedEvent);
+    g_hGETStartedEvent = NULL;
+  }
+
   TaskLock_AcquireExclusive();
 #ifndef ONELOCKTORULETHEMALL
   StatsLock_AcquireExclusive();
@@ -83,8 +92,8 @@ void Reset()
       TerminateThread(g_hThread, ERROR_OPERATION_ABORTED);
     }
     CloseHandle(g_hThread);
+    g_hThread = NULL;
   }
-  g_hThread = NULL;
   g_FilesTotal = 0;
   g_FilesCompleted = 0;
   g_Status = STATUS_INITIAL;
@@ -122,6 +131,13 @@ startnexttask:
   hLocalFile = INVALID_HANDLE_VALUE;
   pFile = NULL;
   TaskLock_AcquireExclusive();
+  // Now that we've acquired the lock, we can set the event to indicate this.
+  // SetEvent will likely never fail, but if it does we should set it to NULL
+  // to avoid anyone waiting on it.
+  if (!SetEvent(g_hGETStartedEvent)) {
+    CloseHandle(g_hGETStartedEvent);
+    g_hGETStartedEvent = NULL;
+  }
   pURL = g_pLocations;
   if (pURL)
   {
@@ -343,7 +359,11 @@ freeurlandexit:
 
     if (!g_hThread)
     {
-      DWORD tid;tid;
+      DWORD tid;
+      if (g_hGETStartedEvent) {
+        CloseHandle(g_hGETStartedEvent);
+      }
+      g_hGETStartedEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
       g_hThread = CreateThread(NULL, 0, TaskThreadProc, NULL, 0, &tid);
     }