Ice_Mage: Did you
open a support ticket like the error message recommends? Others are having the same problem but haven't found a solution:
help me: Error! Galaxy executable checksum doesn't matchmordziaty123: I tried reinstalling it 2 times but still problem exists.
Ice_Mage: Did you perform a clean reinstall, as follows?
1. Uninstall GOG Galaxy from the Windows Control Panel.
2. Open File Explorer and enter
%ProgramFiles(x86)% into the address bar. If the
GOG Galaxy folder has been left behind, delete it.
3. Enter
%AllUsersProfile% into the address bar. If the
GOG.com folder has been left behind, move it to the desktop.
4. Install using
the latest full installer that doesn't download anything from the Internet.
mordziaty123: I installed games to GOG galaxy app and can't open them without it (nothing happens)
Ice_Mage: Did you try launching them by opening File Explorer and double-clicking the game executable in the installation folder? The shortcuts will try to launch GOG Galaxy, so those wouldn't work if GOG Galaxy no longer works.
Edit: fixed typo.
Uninstalled everything just like you wrote, installed it again but still it crashes
mordziaty123: I can open my profile in site, but I installed games to GOG galaxy app and can't open them without it (nothing happens)
I have rebooted my computer 5 times by that time and nothing changed
FrodoBaggins: You don't need the galaxy client. Uninstall it and forget about it.
Download the normal game installers from your account. That's why I gave the link.
I'm saving this option as last resort, but seeing that it's not just me and people have this problem for weeks with no solution Im thinking about doing it soon..