Safari
My browser safari can’t open my web page Zimbra Csf
What is the diagnostic message or error message shown when the connection fails?
Two of the issues that can arise…
If your Zimbra site is using TCP port 10080, you will want to change that port. Most browsers are now blocking access to TCP port 10080. There are discussions of this block around the ‘net, and probably also at the Zimbra website.
If you are using Safari on an older iOS version or an older OS X version, you might be encountering a now-outdated root certificate.