It looks like AutoCAD is running your DLL under a restricted security
policy. Things like writing to disk or connecting to the network might be
restricted by the security policy, which is why you see the error.
Since AutoCAD appears to be the one setting this policy, you might want to
post this problem to the appropriate AutoCAD newsgroup. I do not know how
to get your DLL running with full permissions under AutoCAD.
Doug Redmond
Software Engineer, Autodesk Inc.