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This article applies to Code42 for Enterprise version 5.

Other available versions:

Version 6 | Version 4icon.qnmark.png

Code42 Support

Back up to an external drive

This article applies to Code42 for Enterprise version 5.

Other available versions:

Version 6 | Version 4icon.qnmark.png


Backing up to a local destination, such as an external drive, is recommended when you are frequently using a device in areas that do not have Internet access, or when you frequently need to back up large quantities of data. This tutorial provides step-by-step instructions for backing up files to an external drive.


This article assumes you have permission to manage your backup destinations and add local destinations. Your administrator may prevent destination management or the ability to add local destinations.


Follow these instructions if you would like to back up the files to a folder on your device or external drive:

  1. Open the CrashPlan app.
  2. From Home, select Details.
  3. From device details, select the backup set settings button.
  4. From Destinations, and click Change.
    Backup set settings
  5. Select Add Local Destination.
    The file browser for your device opens.
    Add destination
  6. Select the drive or folder to which you want to back up.
    The new drive appears in the list of available destinations.
  7. Select the local destination that you added.
  8. Click Save.
  9. From Backup Set Settings, select Done.
    CrashPlan begins backing up your file selection to the external drive.


What happens if I disconnect my drive?

You can disconnect external drives at any time, and for any length of time—CrashPlan won't delete the files. When you reconnect the drive, CrashPlan resumes backup from where it left off. If you reconnect the drive and CrashPlan doesn't recognize it immediately, it is likely because the drive letter or name changed. See the troubleshooting tips below to correct the issue.

What happens if my drive becomes full?

If a drive becomes too full for CrashPlan to continue backing up to it, the CrashPlan app reports Out of space at destination. To continue backing up, you can either move the backup archive to a larger drive, or reduce the size of the archive.

How is my local backup stored?

Local backups are stored in the location you selected when adding the destination. They are stored in an encrypted archive format within a folder labeled with the 18-digit device ID that corresponds to your device.

Best practices (Windows)

When you connect an external drive to a Windows device, the operating system automatically assigns the next available letter in the alphabet. If the letter changes when you reconnect a drive you've been using for backup, CrashPlan won't recognize the drive. Consequently, we recommend assigning a static drive letter to your external drive.

Troubleshooting tips

CrashPlan app reports drive as "missing"

This issue occurs when the external drive is disconnected from the device or the letter or name assigned to the drive by your operating system changes. CrashPlan uses absolute paths when backing up. If the CrashPlan app cannot detect a drive at the specified location, such as when it is disconnected or when the name of a drive changes, it lists the drive as "Missing". You can correct the issue by reconnecting the drive or renaming the drive to match the original drive letter or name.

External drive stops backing up (OS X)

If an external drive stops backing up on OS X, it is likely because the drive didn't cleanly unmount (for example, after a power outage, or disconnection without ejection). When this happens, the drive can leave behind a "ghost" folder in /Volumes, even though the drive is no longer mounted. When the drive re-mounts, your device detects that the folder name for the drive is taken, and consequently appends a “1” to the drive name. However, CrashPlan looks for the folder with the original name, which is no longer connected. Use our troubleshooting guide to diagnose and correct the issue.