Oh rats, I was hoping your problem got solved. My problem (GIMP triggers a Windows hard hang) is not the same as yours (GIMP won’t load at all, right?) So my advice might not be useful. Still, here’s what I tried…
In Settings > Updates and Security > Windows Security click on “App & browser control.” Scroll down to “Exploit protection” and click “exploit protection settings.” Select the “Program settings” tab, click “add program to customize” and then “choose exact file path” from the dropdown menu. Find your gimp.exe file to add it, click “edit” and then methodically click all the boxes to “override system settings” and turn off the protections. Honestly, I had no idea what I was doing.
Once that’s done, go to the left-side menu and click “Firewall & network protection” and “allow an app through firewall” and choose gimp.exe again.
Now it’s back to the left-side menu for “Virus & threat protection.” Under “Virus & threat protection settings” click “manage settings.” Scroll down to “Exclusions” and click “add or remove exclusions.” Click “add an exclusion,” choose “folder” from the dropdown, and exclude your GIMP program files folder. Then exclude your GIMP appdata folders (both roaming and local) and also the G’MIC appdata.
There might be still more exclusions buried somewhere in the maze of Windows Security settings. Those are the ones I’ve found.
I have also upgraded my graphics card driver (AMD Radeon) and disabled X-Mouse Button Control (all the crashes happened when I was making rapid mouse clicks and drags). My GIMP has not crashed lately but I am afraid to stress-test it because I’m too busy with the rest of my life to deal properly with this debugging adventure.
GIMP is the only software I use that has a problem on Win 10. LibreOffice, Faststone Image Viewer, Simplenote, VLC media player, Firefox and Thunderbird are stable. If all else fails, I will re-animate my old Win7 desktop and use it offline. And wait for future GIMP Windows builds hoping somebody can figure this out.
If you have Win 10 Pro, maybe try running GIMP in a sandbox? Or set up a virtual machine? At this point I’m just taking shots in the dark.