Error communicating with backend services in MATLAB2021

When downloading Matlab r2021a I get an error and it doesn't want to continue. The installer has created a zip, unpacked but upon set up I get an error message 'Error communicating with the backend services'. I have found the same question on r2020a and they suggested to try legacy_setup.exe but in r2021a it doesn't have legacy_setup.exe how can I do? I don't know how to check antivirus software too and how to disable it. How can I check? Does the antivirus and firewall involved?