Installing JIRA (v7.3.7) and Confluence (v6.2.1) on Windows 2012R2 servers and noted that the installation process created incorrect firewall rules. In order to access the installations from another server we needed to change them.
The firewall crated was for the installation package (allow traffic from atlassian-jira-software-7.3.7-x64.exe for JIRA, atlassian-confluence-6.2.1-x64.exe for Confluence) rather than from the web server (tomcat8.exe.x64). We had to manually fix the firewall rules.