Roku Server Connection Error

[3suns]

Windows 10, MM version 4.1.18.1852
Streaming to Roku 3 using Roku Media Player. Audio files stream ok but occasionally get a server connection error. My bigger problem is with video. I can see the video files but any attempt to play them yields a server connection error.
Media server is enabled and running thru port 56163
Roku is listed as a device and is enabled.
Is there something specific to video files that needs to be set up?

[Lowlander]

ROKU has limited file format (audio/video codec) support, perhaps your files aren't supported by the device. Also check what Auto-Conversion is happening as it needs to be to a format supported by the device.