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CrashPlan Support

CrashPlan Does Not Run On 64-Bit System

Applies to:
  • CrashPlan for Home
Need enterprise or small business documentation?
This article is intended for CrashPlan for Home users. For Code42 CrashPlan and CrashPlan for Small Business documentation, read this page on our enterprise support site.


In many cases, the CrashPlan app's default memory setting supports backing up as much as 1 TB (1,024 GB) of data or as many as 1 million files. However, you may need to assign additional system memory if the CrashPlan app:Unable to connect to backup engine error

  • Does not open when launched
  • Opens, but displays the message: Unable to connect to the backup engine, retry?
  • Closes abruptly while backing up files

This article describes how to diagnose and fix the problem on a 64-bit system to resume successful backups.


  • 64-bit CrashPlan app running on 64-bit Windows
  • CrashPlan app running on OS X
  • CrashPlan app running on Linux

If your CrashPlan app and operating system do not match any of the above, or if you are unsure, see CrashPlan Does Not Run.

Recommended solution for 64-bit systems

If your operating system is 64-bit Windows, OS X, or Linux, follow the instructions below to resolve the issue.

Step 1: Completely uninstall the CrashPlan app

Windows (64-bit)

  1. Open the Control Panel, and select Uninstall a Program.
  2. Select CrashPlan for Home and choose Uninstall.

You may be prompted that another user on the device is signed in. If another user is signed in, it may prevent the CrashPlan app from uninstalling completely. Code42 recommends coordinating with other users to ensure all users are signed out of the account before continuing.

Uninstall Fails
If the uninstallation fails, follow Microsoft's instructions to fix problems that block programs from being installed or removed.
  1. Remove the following directory from your device:
    • If installed for all users:
      • Windows Vista, 7, 8, Server 2008, and Server 2012: C:\ProgramData\CrashPlan
      • Windows XP: C:\Documents and Settings\All Users\Application Data\CrashPlan
    • If installed per user:
      • Windows Vista, 7, 8, Server 2008, and Server 2012: C:\Users\<username>\AppData\<Local or Roaming\CrashPlan
        Depending on your network environment, user profiles can be either Local or Roaming.
      • Windows XP: C:\Documents and Settings\<username>\Application Data\CrashPlan


  1. Open the Finder.
  2. Press Command-Shift-G
    A Go to the folder dialog box appears.
  3. Paste this text into the dialog box:
    • Installed for everyone: /Library/Application Support/CrashPlan/
    • Installed per user: ~/Library/Application Support/CrashPlan/
  4. Click Go.
  5. Double-click Uninstall.
  6. Follow the prompts to complete the uninstall process.
  1. Remove the following directory from your system:
    • Installed for all users: /Library/Application Support/CrashPlan
    • Installed per user: ~/Library/Application Support/CrashPlan


  1. Download the latest version of CrashPlan for Home.
  2. Uncompress the TGZ file to Downloads.
  3. Open Terminal and enter:
     cd ~/Downloads/crashplan-install
  4. Press Enter.
  5. Then enter:
    sudo ./ -i /usr/local/crashplan
  6. Press Enter.
  7. At the prompt, type YES to uninstall and press Enter.
  1. Remove the following directory from your system: /var/lib/crashplan

Step 2: Reinstall the CrashPlan app

  1. Download the latest version of CrashPlan for Home using the links below:
  1. Once the download completes, unzip the installer.
  2. Run the CrashPlan Installer:
  • Windows: Double-click the CrashPlan EXE file.
  • OS X: Double-click the CrashPlan DMG file, then double-click Install CrashPlan.
  • Linux: Run the installer using this command: sudo ./
  1. Follow the prompts to complete the installation.
  2. Once the installation is complete, choose Existing Account on the sign in screen and enter your CrashPlan account information.

Additional installation information is available in the Installing CrashPlan article.

Step 3: Open the CrashPlan app

  1. If the CrashPlan app opens, continue to Step 4 to update memory settings in the CrashPlan app.
  2. If the CrashPlan app does not open, or if any one of the above-described symptoms reoccurs after following Steps 1 and 2, then contact our Customer Champions for further assistance.

Step 4: Update CrashPlan memory settings

  1. Determine how much memory your CrashPlan app needs:
Backup Selection Size Recommended Memory Setting (MB)
1.5 TB or 1.5 million files 1536
2 TB or 2 million files 2048
2.5 TB or 2.5 million files 2560
3 TB or 3 million files


  1. Double-click the CrashPlan logo in the upper-right corner of the CrashPlan app.
    The CrashPlan command-line area opens.
  2. Enter the command:
    java mx nnnn,restart
    where nnnn is the new memory setting.

Command Line Memory Setting

  1. Press Enter.
    The CrashPlan app closes. The CrashPlan service stops. Then the CrashPlan service restarts.
  2. Open the CrashPlan app.
  3. If the CrashPlan app opens successfully, continue to Step 5.
  4. If the CrashPlan app does not open, or if any one of the above-described symptoms reoccurs after following Steps 1 and 2, then contact our Customer Champions for further assistance.

Step 5: Reconnect your backup by adopting

If the CrashPlan app opened successfully, you must now reconnect your CrashPlan app to the backup archives created before the symptoms occurred.

  1. In the Continue Backup message, click Adopt.
    I don't see the option to Adopt.

    Click Adopt

  2. Select the computer that you want to adopt.
    If you're not sure which computer to adopt, check out these adoption tips.

    Adopt Options

  3. Enter your Email and Password again and click Sign In.
    The Adoption Complete! message displays.
Is My Backup Starting Over?
After adopting a previous computer, a scan launches to compare the contents of your backup file selection against your existing backup archive. It may look like your files are backing up again, and the estimated time to complete may seem unusually long. However, CrashPlan uses data de-duplication to identify what is already backed up. CrashPlan will only back up what has changed (For example: folder paths if files have moved, new files). This is a normal part of CrashPlan's operation, but if you are concerned, there are several ways to confirm that your backup isn't starting over.