Windows 10 updated October/November 2017 which will break FFXIV for players using Windows 10N giving a missing WMVCORE.DLL message.

Microsoft provides a patch to add the missing DLLs, but it must be a match with the current update. For the October / November 2017 update:

https://support.microsoft.com/en-us/...n-october-2017

Sorry if this is already mentioned but it gave me very much grief and I wanted to make sure others knew.