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Code42 Support

Unable to back up files (Mac)

Applies to:
  • Code42 CrashPlan (previously CrashPlan PROe)


Never reaching 100% backed up is a key indicator that Code42 CrashPlan cannot back up one or more files. This troubleshooting article describes how to identify files included in your file selection that cannot be backed up on OS X.


CrashPlan app running on OS X

Under the hood

Typically, when files fail to back up on OS X, it's due to the type of files selected for back up. Many of the files that cannot back up are located in the following folders:

  • /Library
  • /System
  • /Applications
  • /Users/<User>/Library

Files located in these folders contain system files that your device needs to operate. CrashPlan is designed to back up and restore personal files, not system and application files. If your backup file selection includes these locations, it could interfere with the priority your crucial files are backed up.

For example, files found in your Library folder are mostly temporary or cache files. CrashPlan prioritizes the most recently changed files first. This causes CrashPlan to spend too much time trying to keep up with constantly changing cache files (like your web browser cache). This can hinder the progress of more important files you truly want backed up.


You can use either of the methods below to identify which files are failing to back up.

Determine what's not backed up (basic)

  1. Open the Finder.
  2. Press Command+Shift+G, and paste the following file path into the dialog:
    • Installed for everyone: /Library/Logs/CrashPlan
    • Installed per user: ~/Library/Logs/CrashPlan
  3. Press Enter.
  4. Open the backup_files.log.0 file with TextEdit.

This document lists every file that CrashPlan has backed up. However, any log lines beginning with a "W" signify a file CrashPlan wasn't able to back up at that time.

Determine what's not backedd up (advanced)

  1. Open Terminal.
  2. Enter the following command:
    • Installed for everyone: grep "^W" /Library/Logs/CrashPlan/backup_files.log.0 | less
    • Installed per user: grep "^W" ~/Library/Logs/CrashPlan/backup_files.log.0 | less

This command lists any file that failed to back up using CrashPlan.

Recommended solution

Modify the CrashPlan file selection to include only personal files.