Need to convert EDI .clm files, 999 and 277. What do I download?
A .clm file is actually a plain text file that contains various text. It can be opened with almost any text processor, but I've seen that users prefer to open it with the help of Excel since excel is working with spreadsheets and it's more conveniently to arrange the data.
If you don't have Excel, then install OpenOffice which is a good alternative as well: http://openoffice-org.software.informer.com/
