From: Lachezar Dobrev <l.dobrev_at_gmail.com>
Date: Tue, 22 Jul 2014 14:14:36 +0300

  I've hit a deployment error with 'GlassFish Server Open Source
Edition 4.0 (build 89)':

> An error has occurred
> Error occurred during deployment: null. Please see server.log for more details.

  It turns out the error is due to a space in the "Application Name:"
field when deploying.