Those are illegal characters in file names on the Windows operating system. You will not be able to extract it beyond "Skip most errors" on Windows.
You could use Linux in a virtual box or live CD to extract the archive. The \ character would be a legal character for Linux. On second thought, you would have to go with a virtual box, the live CD would still be trying to write to a Windows disk.
The only other way I can think of is to rename them on the website, which is probably running on a Linux server, then repeat your backup.
Dale L. Brackin
Support Specialist
English: native
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