The game is extremely buggy in general. Even if you launch it, it has a memory leak issue where it will just crash every hour or so.
A solution is to download the community patch, which solves most of the issues. Beware however, because it makes a decent amount of gameplay changes, which may not be to everyone's liking.....
EDIT:
Also check your task manager for running instances of Sacred client. If it doesn' launch, just terminate every instance of the client and then try to launch it.
Post edited January 07, 2019 by idbeholdME