After I upgrade a multi-server install of Zimbra 6.0.8 to 7.0, I encountered this when running zimbra in proxy server. All other servers (ldap,mta,mailbox) upgraded successfully. The proxy server also upgraded but it does not start imapproxy and nginx due to below error. Looks like it added an extra "conf" on the path.
Starting nginx...nginx: [emerg] open() "/opt/zimbra/conf/conf/nginx/includes/nginx.conf.main" failed (2: No such file or directory) in /opt/zimbra/conf/nginx.conf:5