Backup is corrupted

Instructions on how to troubleshoot and resolve issues with corrupt backups

Symptoms

1.  Backup to an archive of version 12 format fails with the following message:

The file is corrupted

2. You expand activity details and in the line "Failed to open archive" you see a file with .tibx extension, for example:
error 0x400355: Failed to open archive 'Acronisbackup.tibx'.

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