Cups is not printing with "Filter Failed" message -- how to get more info?

For Ubuntu 14.04 users (and maybe others) you cannot add the foomatic-filters as suggested above, as they conflict with the CUPS project's version (cups-filters).

The hint may be in /var/log/cups/error_log. In my case, the output looks like this

[17/Aug/2014:12:47:31 +1000] [Job 83] JCL: 12345X@PJL 
[17/Aug/2014:12:47:31 +1000] [Job 83] <job data> 
[17/Aug/2014:12:47:31 +1000] [Job 83] sh: 1: hpijs: not found 
[17/Aug/2014:12:47:31 +1000] [Job 83] GPL Ghostscript 9.10: Can't start ijs server "hpijs" 
[17/Aug/2014:12:47:31 +1000] [Job 83] renderer exited with status 1 
[17/Aug/2014:12:47:31 +1000] [Job 83] Possible error on renderer command line or PostScript error. Check options.Kid3 exit status: 3

It can be solved with:

sudo apt-get install hpijs-ppds printer-driver-hpijs

Not sure if both are needed, I just picked all hpijs-like things in Aptitude.

Since this is a top hit on Google for "debian jessie filter failed" I'm going to add what helped for me.

This is for Debian Jessie and CUPS failing with "filter failed"!

The culprit was the ghostscript package from stable (i.e. Jessie in this case) which crashes a lot. I upgraded to the ghostscript package from testing.