To improve Windows’ efficiency, beginning with the April 2018 Update, the Japanese IME and the Traditional Chinese IME dictionaries will be moved to Features on Demand (FOD) if you are not also respectively running a Japanese or Traditional Chinese version of Windows 10. If you are running a Japanese or Traditional Chinese version of Windows, you will not be affected by this change. But if, for example, you are running an English version of Windows, when you first add the Japanese IME or Traditional Chinese IME, you won’t be able to immediately type using the IME while the dictionary is busy downloading in the background. Due to this delay while the IME dictionaries are being downloaded, you may see the following symptoms:
1. You may not be able to type Japanese or Traditional Chinese characters when first signing into your account. During the setup screens while installing the April 2018 Update, you might not initially be able to type an account name that includes Japanese or Traditional Chinese characters on a non-Japanese or non-Traditional Chinese OS.
2. You may not be able to type Japanese or Traditional Chinese characters if you do not have an Internet connection or before the dictionary is downloaded. An Internet connection is required to use Features on Demand. Once you are connected to the Internet, the IME dictionaries will start downloading, but it may take a few minutes. You will be notified before the downloading is finished.
3. Windows server update services (WSUS) may not detect your Japanese or Traditional Chinese IME in some corporate environments. WSUS enables system administrators in corporate environments to manage the distribution of updates and hotfixes. Windows server updates may not detect your IME dictionaries in some cases.