I agree with EVERY person who has written that there is no TRUE security when you empty your trash. I was ONLY giving those who miss "Secure Empty Trash" with El Capitan a way to empty their trash cans without error messages.
The fact is that there is digital dust and frags left on your hard drive that can be detected ANY time you empty your 'trash', whether it is "Empty Trash" or "SECURE EMPTY TRASH". So the concept of "Secure' is TOTALLY FALSE. The ONLY way to even THINK that you MAY've actually not left anything in your free space is to consider using an app LIKE "Shredlt X" IF you set your preference for cleaning your free space on your disc to NSA, DoE, and/or DoD standards. I use this every three days to every week, depending on what I'm working on...to clean all of that 'digital dust' and the frags that basically get written over when you simply "Empty Trash". However, I STILL DO NOT have ANY illusion that even THIS app will do the WHOLE JOB on a regular hard drive (this is NOT about SSDs). I did NOT mean to imply that "Secure Empty Trash" ACTUALLY SECURELY EMPTIES YOUR TRASH ON A REGULAR HARD DRIVE. As has been noted by several who commented, dealing with this on an SSD is a totally DIFFERENT ISSUE, which I will not BEGIN to cover here. My comments were ONLY to those who COULD NOT EMPTY THEIR TRASH WITHOUT ERROR MESSAGES, NOT TO LET INDIVIDUALS KNOW THAT ANYTHING I WROTE ACTUALLY INSURED THAT "SECURE EMPTY TRASH" (in previous OS, e.g. Mavericks, etc.).ANY idea that they were ACTUALLY 'SECURELY' emptying their trash. My comments were ONLY to give those individuals who were UNABLE empty their trash with El Capitan without the MISNOMER "SECURE EMPTY TRASH". ACTUALLY, THE NOTION OF 'SECURITY' ANYWHERE IN CYBERSPACE is UNREAL. EVEN if you use a VPN (Virtual Private Network) AND use an app such as I mentioned like "Shredlt X", ANYTHING YOU WRITE ON YOUR COMPUTERS (OR DEVICES--MOST, NOT ALL OF US HAVE SOME KIND OF CONNECTION BETWEEN OUR DEVICES AND OUR COMPUTERS) IS OPEN TO SCRUTINY BY SOMEONE/ANYONE who has the skill to copy/hack/hijack or otherwise 'violate' any of your computer/device information.