I have two consecutive lines of code both of which functioned until I loaded AutoCAD 2004DX over AutoCAD 2004 as part of an upgrade from Inventor7 Pro to Inventor8 pro. They are in a VB6 project The lines are : ObjDoc.Application.ActiveDocument.FullName For cntx = 1 To ObjDoc.Application.ActiveDocument.Blocks.Count - 1 (Note the second line has word wrapped). The first line still executes but the second comes up with an unable to load DLL error. Any Ideas which DLL's block references access under VB6. The autocad typelib reference did not appear to change its description on upgrade and still says AutoCAd 2004 type library (not 2004DX). Any help would be greatly appreciated. Regards Phil