Help:VE176

The tag tagname in containername must have a texture file extension.

The tag is a reference to an image file, but the reference must be to a texture file.

For example, the config file text

kind                                    "industry"
trainz-build                            3.5
light                                   1
nightmode                               "lamp"
icon-texture                            "industry_icon.tga" 

would be flagged with the error

! VE176: The tag 'icon-texture' in 'industry' must have a texture file extension.

The fix is to create a file 'industry_icon.texture.txt' with file contents

Primary=industry_icon.tga
Tile=st

and change the line in config.txt to

icon-texture                            "industry_icon.texture"