: Ensure every file part (e.g., filename.7z.zaa , filename.7z.zab ) is in the same folder . Use 7-Zip : Right-click the first part ( .zaa ).

Select > Extract Here (or "Extract to [Folder Name]").

: Standard 7-Zip splits usually use .001 , .002 . However, some older versions or specific encoders use alphabetical sequences like .zaa , .zab .