Hi all,
Just to let you know that I've had the same issue for several months, including Windows Photos...
simply saying it can't find any photos on my device;
finds something but then stays a 0 for an eternity and never moves on;
finds all the photos but then freezes at that point and doesn't allow me to select the photos to download;
lets me downloads the photos (once in a blue moon) but then crashes midway through.
I've tried two different laptops and two different iPhones - same issues.
I've followed all of the solutions I've seen on this thread (well not all, I've not read all 11 pages) and none have worked for me.
While I don't have a solution to fix this issue, I have overcome it by downloading FastStone Image Viewer which is free for personal use. It only appears to download images in the device's native format (HEIC for an iPhone) but it downloads the photos the way I downloaded them in Windows 10 (organising photos in folders by date YYYY-MM-DD) and that's all I actually wanted. I never knew about HEIC and stuff like this until the problem and I must say I prefer it - saves so much on file size!
If you do download this software and want to convert the images to JPG, the software has an inbuilt batch converter but it doesn't seem to work. I've tried multiple times but it keeps failing. However, as I'm happy to keep them as HEIC, no biggie.
One final issue - if you have the most recent update of Windows 10 (anything after October 2018, apparently) Windows Photos is supposed to have an HEIC extension installed. Even though I have this, the photos were not viewable. A quick Google told me to install the extension from the Microsoft App store...
HEVC Video Extensions from the Device Manufacturer
Note: When I tried to install the 'HEIF Image Extensions', it did say it was already installed.
Install both and you'll be able to see you images and videos.
Hope this helps until Windows Photo is fixed