GpuDeviceCount fails to report the correct number of GPU devices (8, Tesla K80), how can I resolve this?

I am having a problem with a 8 GPU Nvidia Tesla K80 system. It is a shared resource between multiple users which log on to the same machine. I have two other versions of Matlab successfully running on two of the gpus of the K80 system but when I run gpuDeviceCount in a freshly opened version of Matlab ...I am getting an error... looking inside gpuDeviceCount at the error that parallel.gpu.GPUDevice.count gives: parallel:gpu:device:UnknownCUDAError An unexpected error occurred during CUDA execution. The CUDA error was:CUDA_ERROR_OUT_OF_MEMORY

Does anyone know what could be occuring and how I can resolve this?

System: Windows Multipoint Server 2012 Nvidia driver ver: 23.21.13.8819 Intel Xeon 2698 Tesla K80 - 8 GPUS

[Joss Knight]

You should contact tech support about this issue since it sounds like your system is incorrectly configured and/or installed. They can give you some basic test code to run to make sure that the CUDA driver is functioning and can see your cards.