fentonfromcollegeville wrote:
Sorry, but the OS won't allow the exec file which you write about to be deleted. The file won't even stay unlocked. I'm using "El Capitan. Man, how I hate the "Mail" program.
System Integrity Protection (SIP) will not allow core componets to be deleted. Too many people delete things thinkking it is a good idea, and brick their Macs, OR malware replaces core components with modified versions and trick users into doing things.
The smart thing to do is run Mail, and change the Preferences to specify a different app as your default mail app, then just forget about Apple Mail. Don't configure it, Do not setup any accounts, for Mail, etc...
If you insist on deleting SIP protected things, then Google "OS X Disable SIP" and you will find instructions on how to get SIP out of your way.
PS. It would also help if you asked El Capitan questions in an El Capitan forum, instead of mixing your stuff in a Mavericks forum that has a different execution environment.