To extract or view the files within, you will need software capable of opening .7z files, such as 7-Zip , WinZip , or PeaZip .
If the "Unfixable" in the name implies the archive is broken, damaged, or throwing a CRC error, you can try: FestivalPatronageHauntUnfixable.7z
If the header is damaged, 7-Zip has built-in tools, but they are limited. To extract or view the files within, you
(e.g., "CRC Error," "Unexpected end of archive," "File not found.") such as 7-Zip