In this article, I will show you how to fix Lost Ark not Starting/Launching on Windows
First you have to Verify integrity of game files, to do that right-click on Lost Ark and press Properties
After that go to Local Files and Verify integrity of game files
You also have to put a command on General and Launch Options
The command is:
-fullscreen
You also have to make sure that your Windows and Graphics Driver are up to data
Second think that you can try is to check Disable full-screen optimisations
To do that you have to find:
Program Files > Steam > steamapps > common > Lost Ark > Binaries > Win64
After that right-click on LOSTARK and press Properties and Compatibility
On Compatibility you have to check Disable fullscreen optimizations
I am hoping that after reading this article you managed to fix Lost Ark not Starting/Launching on Windows
For a more in-depth explanation, you can watch the video below from the youtube channel.