hi, I modified my .htaccess file to allow browser caching and then I get a a 500 server error with this in the log (ubuntu 14 installation)

[Thu Feb 05 03:54:37.736036 2015] [core:alert] [pid 25624] [client 58.10.145.197:42018] /var/www/.htaccess: ExpiresActive not allowed here

I see that other people have asked similar questions, but I can't seem to find an answer that works.

Thanks.