I've just had this exact problem. Flashing green light when any SD card was inserted but working camera without a card.
The solution for me was to factory reset the camera, format the SD card in another canon camera (I used an old 550d). Then the EOS-M booted without the green flashing led.
I was then able to reinstall firmware and magic bullet. Everything works properly now.
The solution for me was to factory reset the camera, format the SD card in another canon camera (I used an old 550d). Then the EOS-M booted without the green flashing led.
I was then able to reinstall firmware and magic bullet. Everything works properly now.