It took me 4 days and 7 clean installation to figure out this bug! Task Scheduler popup with error message "XXXXXXX: The task XML contains a value which is incorrectly formatted or out of range." when the time zone change to any XX:30 and XX:45 [Example: (UTC +05:30)] If you change the time zone to any XX:00, the error doesn't come up! Need confirmation on this!!! Please post result!! Update: From Microsoft Community The cumulative update KB3081436 of Aug 10, 2015 has resolved the issue. (Haven't tested yet)