clEnqueueTask & image format

I was doing data parallel computing with “clEnqueueNDRangeKernel” in the same kernel and i wanted to change to task parallel computing with “clEnqueueTask” in different Kernels.

But i can t make it work! (was working before with the other way ie: data parallel)

Here is what i have: error -30 when reading image back (#define CL_INVALID_VALUE -30)

		_ciErrNum = clEnqueueTask(_clCommandQueue, _clKernel[i], 0, NULL, &_GPUExecution[i]);

		_ciErrNum = clEnqueueReadImage(_clCommandQueue, _ClImage2, CL_TRUE, origin, region, 0, 0, _image2, 0, NULL, &_GPUDone[i]);

Any idea is welcome !!!