SHIELD Tablet will not connect ADB - only connects as media device

My SHIELD tablet has stopped connecting as a development device. Dev options are set and it worked last time I tried. It connects as a portable media player. There’s no dev icon on the SHIELD and ADB doesn’t connect. I cannot update the driver in Windows (7, 64 bit) to the downloaded nVidia driver, nor to the Google ADB driver. If I disable MTP connection over USB, the device is not found. My Nexus 7 connects fine as a development device.

Hi User,
First sorry for the late reply. Please get the CodeWorks for Android and select the “USB Driver(NVIDIA)->USB Driver for Shield” to install the usb driver for shield.
Any more question, please let me know.