Most part of our products is activated online automatically. In some cases you may need to manually activate your standalone license product using an activation code provided by Autodesk. When you need an activation code you usually send the request code provided by the software during the activation at launch. The request code is usually displayed on screen and it is a 32 digits alphanumeric string.
MotionBuilder 2014 on a Linux OS uses a different activation method where the activation code is not based on a request code but on an .xml file.
The XML file MOBPRO2014en_USLongCode.xml is created during installation on you filesystem's /tmp folder.
So, if you need an activation code for MotionBuilder 2014 on Linux you have to submit this xml file in order to obtain the activation file (MOBPRO2014authcode.xml), that you have to select once you have pressed the Browse button:
To request an activation code or file either point to http://www.autodesk.com/licensesupport or checkout the following article:
General Licensing: Getting an Activation Code Manually