It looks to me like the &quot;can&#x27;t replace&#x2F;delete a file that is opened&quot; is one of the factors that causes the malware phenomenon in Windows. That is, you <i>must</i> reboot to affect some software updates. Frequent reboots meant that boot sector viruses were possible.<p>That policy also means that replacing some critical Windows DLLs means a very special reboot, one that has to complete, otherwise the entire system is hosed.