Missing Microsoft time zones

Question

I'm looking at using the Microsoft time zones (by utilising the System.TimeZoneInfo class in C#) to convert stored UTC dates to local timezone dates and vice versa.

However, I've noticed that this isn't a comprehensive list. For example, it currently only has one timezone defined for Greenland (Greenland Standard Time (GMT-03:00) Greenland), where wikipedia and timeanddate both show there are 2 major time zones in use (eastern and western) as well as 2 lesser used ones.

Is there a comprehensive list anywhere of missing timezones?

Answer 1

The conversion data between Windows time zone IDs and IANA time zone IDs is available via CLDR.

Looking at the data (and at the raw IANA data in Github) it looks like the IANA time zones in question are:

• "America/Godthab" (West Greenland)
• "America/Scoresbysund" (East Greenland)

Those have corresponding Windows time zone IDs of:

• "Greenland Standard Time" (West Greenland)
• "Azores Standard Time" (um, not really East Greenland - read on)

Obviously the Azores and East Greenland are quite a long way apart - but it turns out they follow the same time zone rules, which is presumably why Microsoft has lumped them under a single time zone.

Basically, if you want to find the time in East Greenland for "America/Scoresbysund", then "Azores Standard Time" is your closest bet.