We've checked the logs here and do not see any 403 errors logged. Also as you can access the directory, downloading the files must also be possible. Maybe an antivirus software is blocking downloads of .exe files? Our best guesses are that your network or computer is using an antivirus/security software that is filtering traffic or blocking download of .exe files, that you are not connected to the internet directly but through a proxy from where the 403 is generated, or a VPN that is redirecting traffic to a wrong IP.