Apache Error Log - an unknown filter was not added: includes

Question

I'm getting multiple instances of the following error in my Mac OS X Apache error_log:

[Thu Jun 25 17:11:56.789373 2015] [core:error] [pid 277] [client 127.0.0.1:58739] AH00082: an unknown filter was not added: includes

I've been searching but haven't been able to locate what the cause of this is. Is there a way to get more specific details about what is causing this?

Answer 1

Actually what most likely happened was:

1. You have SetOutputFilter DEFLATE in your config
2. You have NOT enabled the mod_deflate module

In my particular case, I had to simply uncomment this line:

LoadModule deflate_module libexec/apache2/mod_deflate.so

and then all was well.