This morning I found I could no longer switch to the Japanese keyboard layout on my Mac – only the US layout was listed. So I went to System Preferences > International > Input menu and looked for the Japanese Input Method (called Kotoeri on the mac). There was no sign of it; here’s how it got fixed in the end.

Check that it’s a preferences / configuration problem:

• Create a new user (System Preferences > Accounts)
• Log out and log in as new user
• If the input methods are displayed correctly for this other user (see below), it must be a settings issue.

Fix the preferences problem:

• Log back in as the main user
• Drag these two files from /Users/MAINUSERNAME/Library/Preferences to the Desktop:
• com.apple.menuextra.textinput.plist com.apple.system.preferences.plist
• Restart, and presto, Japanese is back on the menu – いただきます！

Note: This is probably relevant for these other Input Methods also, as they disappeared and reappeared along with Japanese (kotoeri):

• Hangul
• Simplified Chinese
• Tamil Input Method
• Traditional Chinese
• Vietnamese UniKey