-- How can include the path for the

Att_http.s4h
$CORE_ROOT/config/attribute

This line should be edited in core_setup file:

EDI_INCLUDE=.;%CORE_LOCAL%\4edi\include;%CORE_ROOT%\4edi\include;%CORE_ROOT%\config\attribute

1. Edit all *.s4 files needed to be compiled with this line:
INCLUDE "att_http.s4h" ONCE;

2. Restart CORE SERVERS;
3. Recompile the MBC.