After installing ESS 4.0 I started getting these super quick pop-ups during the restart/shutdown of XP Pro w/SP3. Didn't matter if I did an uninstall of ESS 3.0 to install ESS 4.0 or a clean install of ESS 4.0 on a OS restored from a clone with no Security/AV applications on it. Since these pop-up were so quick I was not able to identify what was happening till I looked in the Event/System Logs. Here is what it said: Application pop-up: dwwin.exe - DLL Initializatin Failed: the application failed to initialize because the window station is shutting down. More of a nuisance than anything. Otherwise ESS 4.0 appears to be running fine.