I've just tried to install shield on a new ES instance. Running the Step 1 plugin install from https://www.elastic.co/downloads/shield fails and it looks as if it's because the github repo no longer exists.
I just tested installing Shield and the licensing plugin according to the installation instructions on both ES 1.4.5 and ES 1.5. Can you post the error messages you're getting here?
Argh - ignore. Must be my proxy doing something strange; I can get the file.
For reference I'm using ES 1.5.2 on a Windows 7 machine...
>bin\plugin -i elasticsearch/license/latest
Picked up JAVA_TOOL_OPTIONS: ...
-> Installing elasticsearch/license/latest...
Trying http://download.elasticsearch.org/elasticsearch/license/license-latest.zip...
Trying http://search.maven.org/remotecontent?filepath=elasticsearch/license/latest/license-latest.zip...
Trying https://oss.sonatype.org/service/local/repositories/releases/content/elasticsearch/license/latest/license-latest.zip...
Trying https://github.com/elasticsearch/license/archive/latest.zip...
Trying https://github.com/elasticsearch/license/archive/master.zip...
Failed to install elasticsearch/license/latest, reason: failed to download out of all possible locations..., use --verbose to get detailed information
Apache, Apache Lucene, Apache Hadoop, Hadoop, HDFS and the yellow elephant
logo are trademarks of the
Apache Software Foundation
in the United States and/or other countries.