Decades ago, newsgroups were invented for people to post brief, plain-text news stories about their area of research. Today, we shoe-horn giant files into scores of tiny text messages in order to transfer them in the newsgroups. This crazy scheme works remarkably well, however there is one very nagging fly in the ointment: file names.
A newsgroup message has designated spots where the date, subject, poster and other items are placed (just like an email message) but no spot for the filename. So, the posting software will put the filename somewhere in the subject of the post. and a program like ezGroups must then try to find the filename. ezGroups does this by scanning the subject for file extensions. So, it will look for a “.rar” and then a “.avi” and then a “.jpg” etcetera until it finds something it recognizes. Then ezGroups looks at the text before and after the extension to try and figure out the filename, the part number, and the total number of parts.
So, the point of the File Types window is to provide the program with a list of file extensions to look for. The program comes with a list built-in, however new file types are always being invented, so from time-to-time you may need to add one here. Once you do so, you may want to reset the appropriate groups and re-search them.