Who is this article for?
CrashPlan for Small Business
Instructor, no.
Incydr Professional, Enterprise, Gov F2, and Horizon, no.
Incydr Basic, Advanced, and Gov F1, no.
CrashPlan Cloud, yes.
Retired product plans, no.
CrashPlan for Small Business, no.
Overview
If you attempt to start the Code42 app and it displays the message, "Code42 cannot connect to its background service", this article can help troubleshoot the issue. This error usually occurs because the Code42 service is not running.
However, if you see "Unable to connect, check your network" or "Can't connect to server", that indicates a network issue. Network issues occur when the Code42 app cannot communicate with the Internet. To fix a network issue, check that there is no software that conflicts with the Code42 app installed on your system and see Test your network connection (CrashPlan) to further troubleshoot the issue.
Under the hood
The Code42 app consists of two parts:
- Graphical user interface that the user interacts with
- Code42 service that runs in the background
These two pieces communicate over a local network connection that is built into every device. When the Code42 app starts, the graphical user interface and the Code42 service attempt to connect to each other. If they can't connect, the graphical user interface displays an error message.
To learn more about Code42 app status messages, see Code42 app status messages in CrashPlan.

Recommended solutions (all operating systems)
The recommendations below apply to all operating systems. These are the resolutions that most often resolve the issue. If these solutions don't resolve the issue, review additional recommendations below.
Restart the Code42 service
The first thing to try on all platforms is to restart the Code42 service. If this doesn't resolve the issue, try the recommended solutions below.
Out of memory
If you have a large backup selection (more than 1 TB or 1 million files), you may need to allocate more memory to the Code42 app. When the Code42 app runs into this memory limit, the Code42 service is not able to run, resulting in the "Code42 CrashPlan cannot connect to its background service" message. If you have a large file selection backing up, refer to our troubleshooting article on this topic to address the issue.
Remove Code42 app files from previous installations
If the Code42 app was previously installed per user, uninstalling and reinstalling for everyone (the default installation) causes an error. To resolve this issue, complete the following steps:
- Locate the .ui_info file from the previous per-user installation:
- Windows: C:\Users\<username>\AppData\<Local or Roaming>\CrashPlan
- Mac: /Users/<username>/Library/Application Support/CrashPlan
On Mac, the .ui_info file is hidden by default. See Lifewire's tutorial to show hidden files to view the .ui_info file.
- Delete the .ui_info file.
Deleting this file does not harm your backup. It is a file left over from a previous installation and it is no longer necessary.
- Restart the Code42 app notification area or menu bar app:
- Windows: From the Windows Start menu, select CrashPlan > Code42 CrashPlan Tray.
- Mac: Open the Code42 app and select Settings > Show Code42 status in menu bar.
Recommended solution (Windows)
If you are using a Windows device and the recommended solutions for all operating systems didn't resolve the problem, verify that the Code42 service is enabled.
- Open the Windows Start menu.
- Locate and open the Services program: Type services.msc into the Start menu search bar and click Enter.
- Double-click Code42 CrashPlan Backup Service.
The Code42 CrashPlan Backup Service Properties window opens.
- Ensure that the Startup Type is set to Automatic (Delayed Start).
- If the Start service status button is available, click it to start the Code42 service.
- Click Apply if you made changes to your settings, then close the window.
Recommended solution (Linux)
If your system language is not set to English when the Code42 app is installed, the application starts and backs up but fails to open after rebooting the device. To ensure that the Code42 app is able to open after rebooting:
- Uninstall the Code42 app.
- Change the Linux system language to English.
Consult the documentation for your Linux distribution for instructions on changing the system language.
- Install the Code42 app.
- Change the Linux system language back to your language.
The Code42 app will open normally.
Alternative solution
Manually starting the Code42 service after restarting your device will allow you to open the Code42 app.
Starting the Code42 service
Using this method to start the Code42 service will not persist after restarting the device and will have to be reapplied after every restart.