Hello.
I bought The Witcher 3 GOTY in the sales. I could download and install the game using Gog galaxy app but I can't play the game without using the app.
The thing is I want to be able to play the game with and without the app, so Have I to redownload the game without Gog galaxy?
Thanks you.

I don't have galaxy,but probably don't use the shortcut to the game go into the game folder where the game is installed check the exe of witcher 3 try running that or just right click and click properties and check if any options were added in the shortcut or exe and delete what seems to be added in text there.

Or just follow these instructions here https://www.gog.com/forum/general/the_witcher_3_how_to_play_without_galaxy

On the GOG website, go to your library (Click on your user name at the top), and then click on the game you want to download. This will open a window with a list of downloads, simply click on the one you want. You may need to download several files to download the whole game. Using this installer, you can install and run the game without Galaxy.

Alternatively, in Galaxy, go to your library and select 'Backups & Goodies' under 'more', this will give you the same list as before and you can choose what to download.

Finally, you can launch already installed games without galaxy by going to wherever they're installed and running the application directly. Eg: To launch EVERSPACE without using Galaxy I would go to:
C:\Program Files (x86)\GOG Galaxy\Games\Everspace\
And run 'Everspace.exe'.

If you had Galaxy installed when you install Witcher 3 then it detected it and created shortcut using to it.

But as others mentioned it's only the shortcuts that try to launch Galaxy, if you launch the game directly from the EXE file it will work fine without Galaxy. You don't need to redownload anything unless you want the offline installers.

Thanks you for your answers.

I want the offline installers because I want to keep the game in DVD's and put the game on a bookshelve.

There is an option in galaxy to download offline installers (might be called backup or something), so maybe check that for the future.

1. Hover over your username on https://www.gog.com/
2. Games
3. Select the game you want to play
4. Under "Download Offline Backup Game Installers", click on all of the necessary files to save to your PC
5. Install the game files
6. Play

Completely remove Galaxy (hopefully not a fake one) first.

Right, so go to gog.com, where you buy the games, download he offline installers from your account, top of the screen on your username. There will be one exe and perhaps a few non files. Fully download all, and save to a folder and then run the exe.
Games from “other sources” are not legal, and may destroy your system. Also windows store is one thing you will want to remove QuickStart from any machine you have.