Yosemite Server Backup 8.7.01 and higher.
Error 3258 in the Yosemite Server Backup job log refers to Circular Logging in Microsoft Exchange. The text of this error is shown below:
Cannot perform incremental/differential backup - circular logging is enabled. Cannot perform incremental/differential backup ? circular logging is enabled. Please disable the circular logging.
Circular logging is a setting in Exchange that controls how Exchange manages its transaction logs. When this setting is enabled, Incremental and differential backups of Exchange are not possible. The method of disabling this option in Exchange will differ depending on the version of Exchange you are using. Please refer to your Microsoft Exchange documentation on how to accomplish this.
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