: On its own, this file is "broken" or unusable. You cannot extract the contents of part 561 without having all other parts (0001, 0002, etc.) in the same folder. How to Use This File
: Right-click the first file in the sequence (usually 0001.7z or just .7z.001 ).
: The "0561" indicates this is the 561st piece of a multi-volume set.