Suppose that Office 2016 Pro Plus (MS ActionPack, MSDN subscription etc.) is installed on your PC but you still need to add some language support. In my case, I need to add the Russian proof tools to the English Office that includes already the French language support but doesn't contain any Cyrillic spell checking.
The recommended way is to download the language pack and install it. However, it doesn't work for me, the error 30182-4 is occurred. Unfortunately, none of proposed workarounds don't work for me (repair, full reinstall).
The solution is to download a language-specific Office ISO (Russian in my case) available for all MS subscribers and install it over existing English Office. Then go to "Office Language Preferences", add required tools and set options.