Required Port 443 For Veeam Backup & Replication Is Occupied By Another Application ((hot)) May 2026

This error typically occurs during an upgrade to Veeam Backup & Replication (VBR) v13 or newer, where port 443 is now a hardcoded requirement for the Veeam Web Service and API Gateway. 1. Identify the Conflicting Application

Hyper-V Replication: If the server is configured as a Hyper-V Replica server, it may use 443 by default. This error typically occurs during an upgrade to

8. When to Contact Veeam Support

• If no other application appears to be using 443, but Veeam still claims it is occupied (possible Windows HTTP.sys corruption).
• After removing the conflicting app, port 443 remains locked (requires reboot or net stop http /y).
• Veeam services fail even after freeing port 443 (check other Veeam-specific ports: 9392, 9393, 6160, etc.).

After some discussion with the team, they decided to move the Acme Secure Gateway to a different server and change its configuration to use a different port. They also updated the Veeam configuration to use a new port, and everything was back to normal. If no other application appears to be using