[Fixed] Hammer won't launch on Windows 10 20H2?

I recently performed a clean installation/upgrade to Windows 10 20H2 (currentl build: 19042.804) and just found out that hammer.exe won't launch here (it worked under 20H1). Counter-Strike: Source's Hammer works fine but not TF2's. A friend of mine who did a clean installation of 20H2 also seems not to be able to launch the tool.


EDIT (nothing to do with 20H2 after all): https://tf2maps.net/threads/fixed-hammer-wont-launch-on-windows-10-20h2.43714/reply?quote=479249

 

Are there any errors when launching hammer? I know 20H2 is having issues.

 

No, it simply appears as a process in the Task Manager and then crashes soon after. Hammer is supposed to edit a couple of files every time it's launched/closed, but nothing is being changed. I've also run the compatibility troubleshooter but it still won't let it launch at all.

 

Apparently it won't launch if the game itself is yet to install DirectX on first-time setup. Now that I have, Hammer finally runs.