For faster operation, Unison keeps copies of data downloaded from Usenet on your computer for later re-use.
If you experience problems with newsgroup content, or want to reclaim the disk space used by these download caches, you can empty them out.
To empty a newsgroup's cache:
If you clear the cache, Unison will need to re-download content if you return to the newsgroup later.
Downloaded files are not cached, but rather placed directly into your designated Downloads folder. You can use the Finder to delete files from your Downloads folder as you would any other files on your disk.