The DLL is created during the Perl incantation (perl Makefile.PL, make, make test, make install) for XS modules. I'm guessing this was copied there and certainly from WinXP to Win7 you may experience issues and can't just copy a DLL from one system to the other.

Assuming this is the GitHub site you reference, you'll find Perl notes here:

https://github.com/newville/ifeffit/tree/master/wrappers/perl

In reply to Re^3: Invalid Access to Memory location using DynaLoader by VinsWorldcom
in thread Invalid Access to Memory location using DynaLoader by MattN

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