> > > When launching MAMEUI .258 in windowed mode, many games freeze with the following > > > error popup: > > > > > > Unable to create the Direct3D device. (80070057). > > > > > > I'm definitely using the most current version of DirectX and the ONLY time it > does > > > this is when using MAMEUI in windowed mode. > > > > What does MAME do with the exact same settings? > > It runs normally.
It seems 80070057 means that an invalid argument was sent to a d3d function. I'm not an expert (or even a novice) with d3d so I'm unable to advise further.