The Microsoft equivalent of a SegmentationFault.  MoreOrLess. GPF is a memory protection violation (a process stepping on memory not belonging to it). On older versions of Windows, this was a VerySeriousMatter. But WindowsNt and its mutant offspring have "Memory Protection", which supposedly ameliorates the catastrophic nature of this error.

''So, now what happens when we dereference a null pointer on Windows NT? -- StephanHouben''

* You get a GeneralProtectionFault.  In most cases, the program will terminate.  If you have VisualStudio installed, you'll get the infamous "press OK to stop, press cancel to debug" message--one wonders why Microsoft couldn't be bothered to label the buttons "halt program" and "debug program"... at any rate, the important thing is that a null pointer derefence (or any pointer outside the process's address space) will not crash the OS.  In WindowsNinetyFive and such; crashing the OS was an easy thing to do.

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http://www.gpf-comics.com/, if memory serves.

Yep, that's the site for the online comic strip by that name.  Also published on dead trees by PlanNinePublishing.  Intrigue, conspiracy, romance and general geeky wackiness ensue as the strip follows the work and social lives of the employees of the unfortunately-acronym'd company, 'GPF Software'.  Fun stuff.