Unable to launch my Minecraft launcher

Hello,

I'm having trouble launching the Minecraft launcher. It tries to install an update, then tells me it's impossible, attempts to load an older version which doesn't work, and then reports that the problem is due to a lack of internet connection. Another message then says it's due to data corruption. This problem even affects other launchers like CurseForge.

I already opened a ticket in the wrong section, and I was told to open my computer's command prompt and run a repair with the command: "sfc /scannow". I did this, but unfortunately, it didn't help.

What can I do?