Plutonium

khe pasa tronco probably your antivirus or a software blocking the launcher
Try to delete the Plutonium folder in %localappdata% (make a backup if necessary) then add Plutonium to the list of exceptions in your antivirus https://plutonium.pw/docs/antivirus/, make sure that no software is messing with the launcher like a file cloud syncing program and then start the launcher as administrator