Well I spent my lazy and rainy sunday afternoon trying to wrap the native 7z.dll in an AutoIt UDF. I searched the forum and found that it only works with a third party DLL wrapper (rasim's UDF). However, I also came across this codeproject with the following statement: I figured this meant that the problems involving COM and Interfaces was solved and that a third party wrapper was no longer necessary. Then I came across the following prototypes exported by 7z.dll: UInt32 WINAPI CreateObje