This is likely to be a major cause of problems booting or running the game on Windows 11, as well as crashes.

This exploit protection setting is IMPORTANT! Do not disable it globally! Disable it for the Fallout executable only!

1. Open 'Settings'
2. Click 'Privacy & Security'
3. Click 'Windows Security'
4. Click 'App & browser control'
5. Click 'Exploit protection settings'
7. Click 'Program settings'
8. Click 'Add program to customize'
9. Click 'Choose exact file path'
10. Navigate to the Falloutw/FalloutwHR/Fallout2/Fallout2HR executable and select it
12. Ignore all other options, only check 'Override system settings' for 'Force randomization for images (Mandatory ASLR)' and turn it to 'Off'

Enjoy being able to play the game.

It never did that for me.

It defaulted to C:\GOG Games\ (which I changed to D:\Games)

But I use the offline installers. Maybe Galaxy installs are different, but then I would just recommend you don't install under Program Files, and avoid the issues of installing that path.

I expect modern games are fine using "Program Files", but some older games definitely have issues with restrictions there. Which I would think GOG would be aware of.

Sorry I didn't see your reply before now.

No, the exploit protection features in Windows 11 do not apply solely to Program Files; there is no default whitelisting for the Program Files folder, but there IS for the ProgramData folder (a hidden folder that usually contains install info and other misc. data you might not want to touch) and you get similar memory access errors if installed to an external folder on the C:/ drive, ie. C:/GOG/ if Mandatory ASLR is not disabled for the executable. YMMV, however, as I'm using a fresh Windows 11 install with fully modern drivers, protection features and settings; depending on the current threat model, Windows will come with some exploit protection features defaulted on or off.