can't share a file (.chm) but can other files (.pdfs)

in my sharing folder i have some pdfs. their folder appears in the Library and the pdfs make up the number of files i'm sharing -- that is LW says Sharing x files in the bottom left and x is the number of pdfs in the folder that's shared. but i've just tried sharing a .chm file and LW doesn't see it -- the .chm file doesn't appear in the list of files sharing. even after refreshing and even after removing the whole directory from LW and readding it. the pdfs appare fine, but not this chm. i renamed the chm file to pdf (just to see what happens) and LW then shares it :/

why isn't LW recognising/sharing this chm file?

[Lord of the Rings]

Go to LW's preferences>Sharing & add the extension to the list in there & press apply. I don't even know what chm is the extension for. lol I wonder how many others do.

yes that did it -- thanks.

chm is basically yet another document format. i think it's microsoft's and i think it's what they use as help file/documents -- really not sure though. an app/utility called Tubby amoungst probably others converts chm docs to html files. chm looks like it's very similar to html but just wrapped up in one file.