Previous cumulative time zone updates for Windows introduced a discrepancy in the 2011 calendar history of the following time zones:
- Samoa Standard Time
- Russian Standard Time
- Ekaterinburg Standard Time
- N. Central Asia Standard Time
- North Asia Standard Time
- North Asia East Standard Time
- Yakutsk Standard Time
- Vladivostok Standard Time
- Magadan Standard Time
- Kaliningrad Standard Time