Location in the unPoster: Setup Menu –> Settings –> Watcher 2
Posts are kept on a Usenet server for a limited time. When they “expire”, the server removes them. So, even though you may see the files on the Lister, you may not be able to download them. So, when this option is on, the Watcher will delete expired files from the Lister automatically.
Normally, this is what you want – since you can’t download old files anyway, there is no need to keep them around. However, sometimes a Usenet server will malfunction and tell the program that it expired many more files than it really has. If this happens, you will see large numbers of files disappear from the Lister much sooner than usual. If that happens, turn this option off and complain to your ISP. You can keep this option off all the time if you want. For example, after looking at a group in the Lister, and downloading the files you want, you can clear the newsgroup. Or if you have lots of disk space and want to keep all the files for an historical reference, then keep this option off.