Error 205 indicates there is an issue with the file downloaded.  If a firewall or antivirus is preventing you from using the file, you can try disabling if you have them installed. This could also be a firewall on your computers network and not necessarily on your computer itself (ie: work connection firewall). Could you try downloading the file again or see if disabling the firewall helps?

https://helpx.adobe.com/creative-cloud/kb/troubleshoot-download-install-logs.html#error205

if you have a non-current os, your default browser must support tls 1.2, https://helpx.adobe.com/x-productkb/multi/eol-tls-support.html

to test your default browser's tls you can use , https://clienttest.ssllabs.com:8443/ssltest/viewMyClient.html

otherwise, confirm that you can connect to the secure adobe servers by reading, http://helpx.adobe.com/x-productkb/policy-pricing/activation-network-issues.html

do you see both logos after clicking "link"?

if you can and still see a connection error try these steps, https://helpx.adobe.com/download-install/kb/common-network-connectivity-issues.html if those all fail, white list the adobe network endpoints, https://helpx.adobe.com/enterprise/kb/network-endpoints.html

Most Mac users don't install antivirus software although it is available. If you don't have it installed, then this isn't the problem.

do you have an antivirus program installed on your mac.?

and error 205 is a connectivity error.