I'm trying to add some files to an exe file. I opened the exe as an archive with 7-zip and dragged the files in, but it pops up with an error saying "Not implemented." Anyone know why?

Edit: Found a tool that did what I needed with the change of the exe file. So... never mind. Still would be nice to know instead of using an alternate exe file.

Another edit: I just realized I have access to the source files. Silly me....