Downloaded McAfee_Installer_serial_YzmLcQd4MM2qGhffQya1AA2_key_affid_1134_akey from my ISP, optimum.net. Opening the file, the first thing that happens is "Something went wrong with the installation"..
Could not find a download site for McAfee Clean Boot, but I'm 99.9 % certain that the problem is not caused by malware. Windows defender has seen no problems, neither did SuperAngtiSpyware or Malwarebytes.
Downloading the Pre-Install_Tool, running it, and rebooting did not help.
Tried downloading it again and tried to install it with a new file name, but same problem.
Tried downloading it in both EDGE and FireFox (latest update, most used browser) with same problem.