GPU mining with Intel HD Graphics 4000
The following program will show you the OpenCL-capable devices on a given Macintosh:

// clang -framework OpenCL dumpcl.c -o dumpcl &amp;&amp; ./dumpcl

# include &lt;stdio.h&gt;
# include &lt;stdlib.h&gt;
# include &lt;OpenCL/opencl.h&gt;


int main(int argc, char* const argv[]) {
    cl_uint num_devices, i;
    clGetDeviceIDs(NULL, CL_DEVICE_TYPE_ALL, 0, NULL, &amp;num_devices);

    cl_device_id* devices = calloc(sizeof(cl_device_id), num_devices);
    clGetDeviceIDs(NULL, CL_DEVICE_TYPE_ALL, num_devices, devices, NULL);

    char buf[128];
    for (i = 0; i &lt; num_devices; i++) {
        clGetDeviceInfo(devices[i], CL_DEVICE_NAME, 128, buf, NULL);
        fprintf(stdout, "Device %s supports ", buf);

        clGetDeviceInfo(devices[i], CL_DEVICE_VERSION, 128, buf, NULL);
        fprintf(stdout, "%s\n", buf);
    }

    free(devices);
}


If it fails to show you your GPU then its a driver issue.If it succeeds then its some kind of a configuration error.