Your problem is that the archive file is corrupt, truncated, or missing part files.
If you have a multipart archive transfer all of them.
If you do not have a multipart archive, the server most likely gave up while doing the import. Make sure you have enough free disk space for the backup archive and the restored site. If possible, take a backup with a smaller part size (sizes around 250 MiB work for almost all servers), and try again.
If all else fails, you can upload the old-school way: download to your computer, then upload to the other server.
Nicholas K. Dionysopoulos
Lead Developer and Director
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