Q: Having trouble installing OS X El Capitan

Same error here and thanks to @mikeverk I did it :-) My date too was correct to today (March 14th 2016), but I dunno why it ddint like it. NOw setting to date 1124094515 is installing fine... tnx!

OMG! This worked.

I set it back to October 2015 as well. Some random day and time. No error and it installed OK.

Thanks mate.

just type this command to your terminal window:

date 010100002016

this worked for me

Very very STUPID bug because we cannot install El Capitan and more of that WE CANNOT re-download the file !!!

GRRR !  But THANK YOU VERY MUCH for your help with your post - MikeVerk !

oh my, I finally did it. Thank you so much. Apple's "safety features" just freaking me out sometimes

If you have set the correct date and are sure the installer verifies but are still getting error messages when installing try setting the date to the day after you downloaded the installer. This worked forme after trying all the other workarounds suggested here.

This helped too thank you. I just picked a random date and it let me install! Finally!! Thanks

I have tried to amend my time to both today's date & time and have tried resetting my time to previous date according to this website: http://capitalmacservice.com/os-x-installers-cannot-verified-tampered-corrupted/

Problem is I don't seem to be able to change the date in terminal (I have unticked automatic date and time update in settings just in case). Error I get is:

date: bind: Permission denied

date: settimeofday (timeval): Operation not permitted

I have redownloaded all 6gb of this 5 times now and I really need a solution. Please can someone help?    

Bump MikeVerk's SOLUTION up!

I had created a USB installer at least 6 months ago.  It had worked until this week on multiple Macs (I'm in IT). After recreating a bootable USB using DiskMaker X 5, the same error would occur.  I checked the time and it showed the correct time in PST even though I'm in MT.  MikeVerk pointed out that by setting the date BACK to sometime soon after the installer was downloaded, resolved his issue.  I did the same. 

My copy of El Capitan, located in my Applications folder, had a date created of Oct 9th, 2015 and date modified of Dec 4th 2015.  While booted into my USB, I opened terminal and set the date/time to 9:30AM Dec 4th, 2015 (just in case the date modified matters).

As I type this, the install is finishing up.

Nice going all!

I am having the same problem as everyone else. You would have thought I they would have done something to fix the download problem in the past year...

I tried originally downloading the OS to install on an external drive since I was going to wipe my Mac and do a clean install. Kept getting the same message when trying to install as everyone else. The date is fine, but when I tried to verify the download it would tell me it said it did not contain a checksum. I don't want to force install a corrupt system onto my computer. I then proceeded to wipe my computer and get it back to snow leopard (mid-2010 iMac) and still am getting the same problems (was hoping by some miracle the the problem was my computer - with all of its problems - and the issue would resolve itself). Can I buy a disk somewhere?

My other question: Does anyone have the Sierra beta on their computer right now? I am just wondering if I should bypass El Capitan at this point, especially since Sierra is going to be launched this "fall". Pros/cons? I'm about done with El Capitan at this point.