The latest version of Casper Suite, 9.8 is not fully compatible with El Capitan. The issue you're seeing is the same that others have run into when running El Capitan and Casper Suite 9.8. See this thread for example. Not even sure if that's the version of Casper you have on your JSS since you didn't mention it. Regardless, you'll need to wait for 9.81 or later to be able to fully use 10.11 and JSS/Self Service. etc.
JAMF is aware of these issues and should have it fixed by the time the full release of 10.11 drops and they release a compatible version.

I had the same issue. Found that it was a problem with the read-only account on the File Distribution Point. JSS was setup using the User credentials for the Read-only account, switched it to the username and now it works.

I was having this issue as well.

JAMF support provided this defect number. D-009498

Regards,
TJ

@mm2270 .. sorry, yes I am on Casper Suite 9.8... Thanks for the info provided, that answers my question.. Appreciate everyone's feedback on this... I will just await until 9.81 or later comes out...

9.81 doesn't fix it, FYI. I still have the issue. Looks like the share doesn't get mounted, so it fails outright.

I had the same problem before where my DP does not get mounted when installing an app from Self Service. My technical account manager suggested to add a wait command (sleep 60; kdestroy -a) for each trouble policies.
This is working for me, Jamf is working on a solution for this problem.

I had the same problem before where my DP does not get mounted when installing an app from Self Service. My technical account manager suggested to add a wait command (sleep 60; kdestroy -a) for each trouble policies.
This is working for me, Jamf is working on a solution for this problem.

We have had this issue since moving to 9.71 back in April. While adding that command to the end of all your policies helps, we were still running into issues. The only 100% foolproof way I have found is to create a script that runs prior to any attempt to mount an SMB drive and then call the actual policy using a custom trigger. Basically it means 2 policies for something that should only take 1 policy. It's a pain to manage and I look forward to when this issue is fully resolved. It's been a long 6 months!

Have you tried running the installer directly on your El Cap machine? I'm the last person on the planet not using Evernote, so does anything in the installer use any of the protected directories?

I was seeing this issue with 10.11 and 9.8.1 until I removed the files in /Library/Application Support/JAMF/tmp
Might also try clearing anything JAMF-ish in /Library/Caches or ~/Library/Caches.

Thanks @ega
I just removed the tmp folder and restarted and it worked like a charm. Not a workable solution for an entire organization, but it's certainly a start for those few early adopters that ignored our requests not to update. :)

@ega did you delete the entire /tmp folder? I am still getting hit or miss policy fails when installing .dmg from self service.

10.10.5 & 10.11 on 9.81...

@acorn I removed everything inside that folder
sudo rm -Rf /Library/Application Support/JAMF/tmp/
and
sudo rm -Rf /Library/Application Support/JAMF/tmp/.