Alot of the info out there is simply outdated and no longer works. I know this because I've ran into similar problems. Microsoft has changed security things around over the past few years concerning run as Admin and UAC prompts. Does anybody have an idea what else I could try? (I already checked the correct path to speedfan.exe multiple times, followed tutorials step by step and gave it the highest priority, so I have no clue what's wrong)

SpeedFan just refuses to open up with the scheduler. A symbol pops up in the taskbar but disappears again in less than a second (I only see a popup, not even a real symbol) and then nothing happens.

When I create a shortcut or when I just start the schedule manually in the scheduler, then nothing happens. But for me it doesn't work for some reason, I tried it multiple times and with different tutorials. Most of them were solved by creating a new schedule in the scheduler, give it the highest priority and set the trigger to login. I wanted Windows 10 to open it each time I login, so I followed A LOT of tutorials on the internet. However it's extremely annoying to open up SpeedFan after every reboot (with the UAC always asking if I really want to open it) and change the values manually, because SpeedFan doesn't save them for some reason. As I have problems with the speed of my fans I managed to regulate them with speedfan.

Launch speedfan on startup