Lightroom 9.1 doesn't start at all for me on Windows 10.
I updated my video drivers to the latest versions (with a clean reinstall), I reinstalled my CC Apps (also using Adobe Creative Cloud Cleaner tool). I event used an older version of LR (8.4) but still doesn't work.
I found the error in the Windows Event Viewer and it says
Faulting application name: Lightroom.exe, version: 188.8.131.52, time stamp: 0x5de0bfe8
Faulting module name: DirectML.dll, version: 10.0.18362.267, time stamp: 0xd1d24d33
Exception code: 0xc0000409
Now, I checked the official requirements: I am using a supported version of Windows 10 (1903) and my video drivers are DirectX 12 compatible (I also have DirectX 12 installed and I have no problems with it, checked with dxdiag).
I have opened a support ticket but it seems to me that even the support team is clueless. I had to drop the conversation with them today but I'll resume it tomorrow.
This upsets me, especially since LR used to work very well on my PC, but it seems that the November update broke it.