rtContextCreate returns RT_ERROR_INVALID_CONTEXT

I’ve encountered this error on a few different machines, though not the ones I normally use. It seems to generally happen with machines that use older hardware, or machines that contain multiple GPUs if one of those GPUs is older (even if only the newer devices are made visible with CUDA_VISIBLE_DEVICES). Most recently, it came up on a machine with a K2000, which although old, still has compute capability 3.0.

The documentation for rtContextCreate doesn’t list RT_ERROR_INVALID_CONTEXT as a possible return value. Is this a bug, or is there something undocumented in the code? Any ideas on how to debug or work around this?

Running Windows 7, 64-bit, VS2013, OptiX 3.8.0

Incidentally I’ve seen this error on a multi-GPU machine two days ago. The problem was that the OptiX version I used required a newer CUDA driver than currently installed on the machine.
OptiX 3.8.0 was built with CUDA 7.0. Please check if the failing machines have display drivers installed which support CUDA 7.0 or newer.