You need to change the Makefile and add to the INC = string an -I with the path to the instance client's sdk include directory. I also had to add to the LD_RUN_PATH = string the path to the instance client's sdk lib directory. This solved most of the problems I have, by if you look at the thread I entered today I have run into other problems. But they could be problems just installing on cygwin (win NT). Regards.