This is an interesting error message that has happened before with Inventor but now it is happening with Showcase 2014.
An Autodesk product failed to send the required value for SERIALNUM
The error report sent to Autodesk may be incomplete.
To quickly resolve the issue, just check out this blog post:
http://forums.autodesk.com/t5/Installation-Licensing/Showcase-2014-fails-to-open/td-p/4294542
Reference
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