If you are unable to connect to CrashPlan Central or CrashPlan PRO Online, the status indicator for the destination on the Backup tab is typically grey instead of green. Additionally, you may see one of the following messages:
Follow the troubleshooting steps in this article to identify and remedy the issue.
The error "Unable to connect to the backup engine" is usually not a network error. Typically when you see this error, you are unable to open the CrashPlan app. See our Unable to Connect to the Backup Engine article for further troubleshooting.
You can identify and solve network connectivity problems through a process of elimination, shown below. For best results, follow the steps in the order presented.
Start by manually instructing the CrashPlan app to reconnect with the destination. This is an easy catch-all solution that can repair a disruption in the connection. Simply enter the restart command in the CrashPlan app's Command window:
If you're still not connected to the destination, use a simple Telnet command to further diagnose the issue. Telnet allows text-based communication between computers. Here we use it to see if your computer can talk to CrashPlan Central (CrashPlan for Home) or CrashPlan PRO Online (CrashPlan PRO):
telnet central.crashplan.com 443
If Telnet successfully connects, it will display a message similar to this:
telnet central.crashplan.com 443 Trying 126.96.36.199... Connected to central.crashplan.com. Escape character is '^]'. ?cA-18782|com.code42.messaging.security.SecurityProviderReadyMessage??"???Q??????OM???`q?ʯ??N??6C:
If you're able to connect through Telnet, but not the CrashPlan app, it's frequently due to antivirus software blocking the CrashPlan app. It's also possible, but less likely, that your firewall is blocking the CrashPlan app. Proceed to Step 3 for further details on troubleshooting antivirus and firewall software.
If Telnet cannot successfully connect, you may see a "connection refused" message, no response, or some other response. The most common cause that we see for this issue is that a firewall is blocking CrashPlan. Proceed to Step 3 for further details on troubleshooting firewalls.
Antivirus software is designed to protect your system against unknown applications and unauthorized Internet activity. Consequently, you may need to add CrashPlan as an approved application in your antivirus or security software in order for the CrashPlan app to function properly. The following antivirus and security applications have been known to prevent CrashPlan connections.
Firewalls are designed to prevent unauthorized network activity on your computer. Many operating systems come with a built-in firewall:
Your computer may have other software firewalls installed. If you are using a firewall, you may need to add CrashPlan as an approved application, or allow outgoing access to TCP port 443.
To determine if your antivirus software or firewall is blocking access to the destination:
*crashplan.com(using a wildcard in the exception allows traffic to any our servers)
After adding antivirus software or firewall exceptions, open the CrashPlan app to check your connection status. If you are still unable to connect, repeat Step 1: Manually Attempt To Reconnect.
See External Resources below for links to instructions for commonly used antivirus applications, as well as Windows and Mac firewalls.
If you are still unable to connect after resolving any conflicts, a firewall on your router may be preventing the connection. However, it's worth noting that we only rarely see routers causing connection issues for CrashPlan for Home customers backing up to CrashPlan Central or CrashPlan PRO Online. It is more frequently an issue for establishing connections between computers.
If the connection issue persists, please contact our Customer Champion team for further assistance.
Include the following information in your request to help our Customer Champions diagnose the issue faster: