dviout.hlp : dviout on-line help file.
dviout.cnt : contents file for on-line help.
dviout.par : When this is in the directory containing dviout or in the Windows system directory, it is interpreted as the parameter file and read in. It can also be called dviout.ini.
dviout.vfn : This is the name of the default Japanese fonts and TrueType fonts definition file. It is not needed when only the Windows TrueType fonts are usually used for Japanese fonts.
dviout.gss : When this is in the directory containing dviout, it is referenced when [Guess] guesses the location of the font.
***.cfg : Printer definition file (normally not used)
template : File defining the font creation method. The file name is valid when specified by -gen:.
par\***.par : Parameter files refered by Option->Choose Parameters.
par\***.pas : Same as the above but is hidden.
par\***.pgm : Paging macro files refered by [Option] in the printing dialog.
par\***.pgn : Same as the above but is hidden.

The TEXPK, TEXFONTS, TEXKNJ, and TEXFLI Parameters can be defined by environment variables.
If the TEXCFG environment variable is present, dviout.par is searched even in that directory. If the TEMP or TMP environment variable is present, this is interpreted as the directory for creating the temporary files.