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This article applies to Code42 for Enterprise version 4.

Code42 Support

Synchronization and your backup

This article applies to Code42 for Enterprise version 4.


The CrashPlan app stores information about your file selection and the progress of your backup in its cache files. To verify the accuracy of the cache files, the CrashPlan app periodically synchronizes this information with the information stored at the backup destination.

What happens during synchronization?

The CrashPlan cache contains indexes with detailed information on all of the files, versions, and blocks of data you’ve backed up. The synchronization process compares the indexes at the source with the destination, looking for differences. The CrashPlan app then updates the cache and uses the updated information to complete your backup.

Restoring files during synchronization
During synchronization, you cannot back up or restore using the CrashPlan app. See our troubleshooting article for tips on restoring files during synchronization.

When does synchronization occur?

By default, the CrashPlan app synchronizes your local cache with your backup at the beginning of each backup session, or when reconnecting to the server. In addition, there are several conditions that trigger synchronization:

See the synchronization process

Normally the synchronization process runs quickly and you may not notice that it has occurred. If your backup selection or archive are very large, you may see the following process within the CrashPlan app when one of the triggers above begins the synchronization process:

  1. On the Backup screen Synchronizing is displayed under the progress bar.
    The CrashPlan app compares the cache indexes, if they do not match it downloads them from the server.
  2. File synchronization runs.
    The CrashPlan app displays Synchronizing file information (0-100.0%).
  3. Block synchronization runs.
    The CrashPlan app displays Synchronizing block information (0-100%).
  4. Backup and restore resume normally.