1257 - Local copy backup fails with error "Backup failed: newPosition > limit"

Symptom

A local copy backup fails and an error similar to the following is presented:

ERROR : 19:28:28 Backup failed: newPosition > limit: (124776892 > 65536)

Cause

This happens when the local copy of the data gets corrupted, which could be for various reasons. One possible reason is connectivity issues if the local copy is kept on a network drive. We recommend using the local disk for local backups, since this location tends to be more reliable than a network location.

Solution

Run a backup with local copy disabled, then re-enable local copy before running another backup. If this fails, purge the local copy directory completely before doing a fresh backup with local copy enabled.