i am thinking of installing a gog game on laptop aaa and then copying the game folder and transferring it to my other laptop bbb. bbb already has the prerequisite programs installed

will the game run on bbb if i launch it from the .exe file in the game folder?

i did some tests on aaa. i changed the name of the game folder and then i ran the game's .exe file and the game worked

Or you could simply download offline installers from your library, and properly install the game on both machines. ;)

Edit: Changing folder name of the game may not be a good test, many games can store settings, saves, etc. in a different location.

I just wonder if bypassing the installation process would cause a problem registering the game with windows.
I haven't tried something like this in years, honestly, except with portable apps.

I was wondering that too, the %appdata% or wherever the installation puts the user files needs to be present. Not sure if galaxy populates that if you import a new game folder.

Worth a try for op, not hard to import folder assuming you're trying to use galaxy.

https://i.postimg.cc/8NT1WZSs/galaxymovefolder.png

Ink's solution is the preferred one.

the game will be registered in windows if you install it by using the setup file

i want to install the game on aaa by using the offline installer and then transfer the game folder to bbb and play the game on bbb as a portable app. will that work?

The most precise answer you can expect is "maybe".

Most games will likely work without a proper installation process, but there may be some that don't. If you want to know for sure just do it and see if it works.

It might, but unless you don't have admin privileges on bbb, then just download the installer, copy it across and install on bbb.

What you are talking about is “is game x portable”. In a lot of situations no. There are lots of links to registry, other dependancies, and folders. Sometimes it is possible with tweaking. This being said, unless you have a very very specific reason to do this I would not recommend. You could be creating issues later n that are hard to track down. In all cases using the offline installers will be better and more robust.

Just to complete the answer above, most games aren't portable in the sense that you can use them on a pen drive and keep your saves there. But there's many games (mostly indies) that can be transfered after installing by copying the folder, Shadow Tactics is one tried exemple on GOG and most DRM-free I've bother to download from Epic freebies, like Batman games works too.
I would say if the game is not high production value (like AAA) chances are it will work and will create a new save and config files on a new machine.

Most games save on "documents" folder, configuration on "appdata" and sometimes engine data is stored in "appdata".

The free Amazon Prime games downloaded through their games client can be moved around freely like that as well. It is kind of convenient, I can move the game anywhere I want, on any drive and play it from there.

My experience is that it works with most of the games. I often copy game directories from one system to another as GOG stupidly still distribute 64bit games with 32bit installers.

Depends when the game was made. Older games (usually pre 2010) may still need some registry entries, or older dependencies. But newer games should work fine.