Sub Application_Start() ' Let the application know that we have to initialize App.oApp.lApplicationStart = True End SubThen, I am using that flag instead to initialize. This works as before. However, it still has the same very rare issue. Basically, a worker process will go in here on the first hit. Then, it will initialize. But, I just found one worker process who completely skipped the Application_Start(). This resulted that the initialize was never done.