If the extraction fails with a "Checksum Error," it means one of the parts is corrupted. You can often find recovery records or MD5 hashes on the original download page to verify that your download is identical to the source.
If you only have part07 , the extraction will fail. You must locate the preceding six parts.
You can use industry-standard tools like WinRAR or the open-source 7-Zip to recombine these segments.