When attempting to use a plugin with a standard installation of coq, you may have the problem that the compiled plugin is not provided for your linux distribution. This page attempts to provide a few pre-compiled versions of plugins for common combinations of versions for Coq and the underlying ocaml system.
If you have a version of
The Coq Proof Assistant, version 8.2pl1 (August 2009) compiled on Aug 05 2009 17:41:33 with OCaml 3.11.1+rc1then you can use this version of ssreflect.
try using this script