Windows 10 Japanese IME not working with text input

I just installed the Japanese language pack, but I can't get it to work. Whenever I switch to the Japanese keyboard and hit the A button, I receive the error Japanese IME is not ready yet. . This seems to be a rather common error, however none of the solutions I have tried work (re-installing the language pack, adding a key in Run in the registry) and some solutions just reference context menus or control panel sections that don't exist anymore. I enabled switching input language per-window, and I noticed something interesting: The A key will switch to a Japanese character (implying it's worki

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