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This article applies to Code42 for Enterprise version 4.

Other available versions:

Version 6 | Version 5icon.qnmark.png

Code42 Support

What should you back up?

This article applies to Code42 for Enterprise version 4.

Other available versions:

Version 6 | Version 5icon.qnmark.png


This article provides tips and advice for determining what to back up. CrashPlan is designed to back up and restore your personal files from your personal computer. Personal files are the files you create and most commonly interact with directly. They also include certain files created by applications based on your information and settings in those programs.

  • Examples: Documents, photos, music, videos, Outlook messages, web browser bookmarks
  • Location: Typically stored in a User directory or Home folder

Where to start

When you first install the CrashPlan app, it scans your file system and picks the User directory or Home folder as the default file selection. This usually displays on the Backup tab as the name of the user or computer.

This a great folder to start with because your personal files and settings are typically saved here. This includes files you create or add, like documents and photos, as well as your customized settings for various applications.

Seeing what's backing up
Click the name of a folder in the CrashPlan app to quickly see what's included.

For example, the marvin folder selected in the CrashPlan app above includes this user's Desktop, Documents, Downloads, Movies, Music, and Pictures folders, as shown below.

Additionally, although typically "hidden", this folder contains the user's Library, which houses user information like application preferences, bookmarks, and fonts.1 This is similar to the AppData folder found in the User folder of computers running Windows. Even though the Library and AppData folders are usually "hidden" in your file browser, CrashPlan knows to back them up when the User or Home folder is selected.

1If you have installed any non-standard fonts at the system level, consider also backing up those files. The Font folder is located under the System folder on Mac or the Windows folder on Windows. 

Other considerations

If you have questions about backing up a particular type of file, our Backup guide is a great place to start. A few common considerations are listed below.

Back up external hard drives

You can back up external hard drives with CrashPlan. You might also want to create backup sets to back up your external drive on a different schedule than your other files.

Time Machine

CrashPlan and Time Machine complement each other well and they can be used on the same computer, side-by-side, backing up your live data. However, for technical and practical reasons, you shouldn't try to integrate the two. Instead:

  • If you only use Time Machine for backup, then exclude the entire drive from your backup set
  • If you use Time Machine for backup and storage, then exclude the Backups.backupdb folder that contains your Time Machine backup from your CrashPlan backup set

Virtual Machines and boot partitions

Backing up virtual machines (VMs) or separate boot partitions are special cases that may require specific settings. See our guide to backing up virtual machines and special boot partitions for more information.

Deselect files

This default backup set often the covers the majority of what should be included in your backup set. If you are concerned about the size of your backup set, you may choose to selectively remove folders or individual files from this set. You can also choose to remove specified file types from this set, regardless of where they are stored.

User permissions requirement (Windows)

Unless the CrashPlan app is installed per user (version 4.3 and later only), CrashPlan relies on the system user's read/write permissions to access your files. However, there are some files or directories the system user may not have permissions to access. If you need to back up these files or folders, follow our tutorial to add the system user to the permissions list.

What not to back up

CrashPlan is designed to back up your personal files from your personal computer, not system files, applications, or server resources. We don't recommend adding these files to your backup selection because they can interfere with the backup of your personal files. These types of files often have complex requirements and relationships to other files, so it's often useless to restore them.

System files

These are files that your computer needs to work correctly. They may be a part of your operating system, a third-party device driver, or another source. Typically, you don't interact with these files directly.

Application folders

These folders contain the files that allow various applications - like your email, word processor, and web browser programs - to work correctly. Like system files, you don't typically interact with these files directly.

What happens if the entire hard drive is selected?

If you select your entire hard drive as your backup set, including system and application files, these files could prevent your personal files from backing up efficiently.

As part of its normal operation, your computer creates new system and application files, which are small. Because CrashPlan prioritizes its to-do list based on file size and creation date, this data is backed up before other files in your backup selection.

Some symptoms you might see if CrashPlan backs up system or application files:

  • Time to complete backup selection increases, sometimes by many days
  • Backup never reaches 100%
  • Backup status is incorrectly reported
  • No files are displayed on the Restore screen

Still unsure?

Consult our forums or contact our Customer Champion team for additional guidance.