Minecraft launcher fails to launch and getting stuck (both on Windows and Mac)

Ok, yesterday I had a problem of joining my minecraft world due to a weird problem that my launchers couldn't verify products I own, claiming that Internet connection was unstable. Well, I updated all my drivers, restarted computer, used different account and still had the same problem. 

After that I decided to reinstall Minecraft but it made everything even worse, because now I can't even properly launch Minecraft launcher. Every time it says "unable to upload Minecraft Native Launcher" or error code 0x1. I worked with Tech Support from Mojang to help me deal with this problem, but nothing worked. Last time we tried to use troubleshoot but all it did was launching the Launcher (with the message about failed update of native launcher) and getting stuck, unless I close it with the task manager. 

At this point I just giving up since I really don't know what is the problem. To make things worse, my friend also has this issue but she is using Mac (i'm a Windows user), so there is smth wrong with the Minecraft launcher.