# X_TIMEZONE_INVALID

## Means

not an IANA zone

## Typical cause

`CET`, `+02:00`, a single-label legacy name like `Japan` or `GB`, or a typo

## Fix

use `Area/Location`, or `UTC` — a legacy name swaps mechanically (`Japan` → `Asia/Tokyo`, `GB` → `Europe/London`); an abbreviation does not, because it names no jurisdiction and carries no DST rule

[i18n, money, time](/error-codes#i18n-money-time)