Why do I get System.AccessViolationException?

Q:

description: I am currently experiencing the following problem:
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System.AccessViolationException: Attempted to read or write protected
memory. This is often an indication that other memory is corrupt.
--

I am unsure as to wether this is an OS problem or a component problem.
The error is generated on the following line:

PDFDoc pdfout = new PDFDoc();

Other info:
product: PDFNet SDK
version: 3.5 (Demo)
os: MS Vista (VS05)

A:

You need to initialize PDFNet using PDFNet.Initialize() before calling
any other PDFNet method. Please see
http://www.pdftron.com/net/faq.html#pdfnet_init for more info.