: You can use a hex editor like HxD to view the "magic numbers" (file signatures) at the beginning of the file to confirm it is indeed a 7z header.
If you do not have the other parts, you can try to identify what the archive might contain by: LL_102-104-00105.7z.001
The file is the first part of a multi-volume compressed archive created using 7-Zip . : You can use a hex editor like
: The software will automatically combine the parts and allow you to view or extract the original files. Identifying the Contents LL_102-104-00105.7z.001