Required Port 443 For Veeam Backup & Replication Is Occupied By Another Application [top] -

Troubleshooting: Port 443 Conflict with Veeam Backup & Replication

Overview

One of the most common installation and runtime errors encountered with Veeam Backup & Replication is the notification: "Required port 443 for Veeam Backup & Replication is occupied by another application."

Before you can fix the problem, you need to find the "squatter." Since Port 443 is the standard port for secure web traffic, the most common culprits are IIS (Internet Information Services), Apache, Skype, or VMware Workstation. The Quick Fix via Command Prompt: Open Command Prompt as an Administrator. Run the following command:netstat -ano | findstr :443

• Installer originally allows port selection. After install, modify via registry (not recommended – re-run installer config).

1. Open Internet Information Services (IIS) Manager.
2. Expand the server name and click on Sites.
3. Right-click the website (usually "Default Web Site") and select Edit Bindings.
4. Select the entry for https on Port 443 and click Edit.
5. Change the Port to an unused port (e.g., 8443 or 444).
6. Click OK and restart the IIS service (via Command Prompt: iisreset).

"The port 443 required for Veeam Backup & Replication is occupied by another application."

1. Identify reservation via netsh http show urlacl and netsh http show sslcert.
2. Map AppID to a service using registry search or PowerShell (search for GUID).
3. Remove reservation with netsh http delete sslcert and/or netsh http delete urlacl after ensuring service stopped/uninstalled, or reconfigure to other port/IP.
4. Rebind certificate for Veeam: use netsh or Veeam configuration to install cert and allow service account access to private key. Scoring: technical accuracy, safety checks, commands, recovery plan.

Identify the process name by opening Task Manager, going to the Details tab, and sorting by the PID column. Common Conflicting Applications

She realized the truth with a sinking feeling: Veeam, by default, binds to all interfaces. It saw the AcmeCorp agent still technically occupying the port on the secondary IP. Windows Sockets don’t care about your IP segmentation logic—if any process listens on 443 on any IP, no other process can bind to 0.0.0.0. A cold war over a single integer.

"Required port 443 for Veeam Backup & Replication is occupied by another application."