When upgrading the SEPM from version 12.1 RU1 MP1 to version 12.1.2, the following error appears "Error 1920. Service W3SVC (W3SVC) failed to start."
you know what? ...
This issue has been solved in the MP1 for 12.1 SEPM, but it´s repeated in the last Upgrade to 12.1.2 ... this is so sad Symantec ...