2.2.47 [RFC5545] Section 3.6.5, Time Zone Component
The specification describes the VTIMEZONE component.
Microsoft Office Outlook 2007, Microsoft Outlook 2010, Microsoft Outlook 2013, Microsoft Outlook 2016, Microsoft Outlook 2019
On import, Outlook attempts to approximate VTIMEZONE components to a VTIMEZONE with one annually-recurring standard-to-Daylight Saving transition date, and one annually-recurring Daylight Saving-to-standard transition date. The approximation process is specified in [MS-OXCICAL] section 126.96.36.199.1.19. Only the following properties are used to approximate a VTIMEZONE, all other properties are ignored: TZID (in VTIMEZONE components), DTSTART (in DAYLIGHT or STANDARD components), RRULE (in DAYLIGHT or STANDARD components), TZOFFSETFROM (in DAYLIGHT or STANDARD components), and TZOFFSETTO (in DAYLIGHT or STANDARD components). If a time zone cannot be approximated or parsed, it is ignored.