Universal Media Server is a DLNA-compliant UPnP Media Server. UMS was started by SubJunk, an official developer of PMS, in order to ensure greater stability and file-compatibility. The program streams or transcodes many different media formats with little or no configuration. It is powered by MEncoder, FFmpeg, tsMuxeR, AviSynth, MediaInfo and more, which combine to offer support for a wide range of media formats. Because it is written in Java, Universal Media Server supports all major operating systems, with versions for Windows, Linux and Mac OS X.
When using the default options in UMS, no codecs are needed. The only time you need codec is to use the AviSynth engine. In that case K-Lite Mega Codec Pack is recommended. If you already have codecs or a codec pack installed, uninstall them first and restart the computer before installing K-Lite. In the installer options select "Lots of stuff", the rest can be left at defaults.
To see a comparison of popular media servers, click here