Required Port 443 For Veeam Backup & Replication Is Occupied By Another Application Access

Critical Error: "Required Port 443 for Veeam Backup & Replication is Occupied by Another Application" – Causes and Fixes

Step 4 – Verify Veeam service status

Get-Service Veeam* | Where-Object $_.Status -eq 'Running'

If Veeam Backup Service is stopped, port conflict is likely.

Phase 1: Identify the Conflicting Process

Do not guess. Use Windows built-in tools:

Step-by-Step Troubleshooting Guide

Step 1 – Identify the process using port 443

Run as Administrator in PowerShell or CMD: Critical Error: "Required Port 443 for Veeam Backup

netstat -ano | findstr :443

Example output:

TCP    0.0.0.0:443       0.0.0.0:0      LISTENING       1234
TCP    [::]:443          [::]:0         LISTENING       1234

Note the PID (1234 in this example).

How to Diagnose via Command Line

If the error message does not specify which application is holding the port, you can identify it using Windows built-in tools.

Using Command Prompt (netstat):

  1. Open Command Prompt as Administrator.
  2. Run the following command: 
    netstat -ano | findstr :443
  3. Look for a line ending in LISTENING. Note the PID (Process ID) number on the far right.
  4. Open Task Manager, go to the Details tab, and find that PID to see the specific application name (e.g., w3wp.exe indicates IIS).

Using PowerShell: Run the following command to see the process name directly:

Get-NetTCPConnection -LocalPort 443 -ErrorAction SilentlyContinue | Select-Object OwningProcess, State | Format-Table

Scenario B: It's SQL Server Reporting Services

  1. Open Reporting Services Configuration Manager.
  2. Connect to the report server instance.
  3. Click Web Service URL.
  4. Change the TCP Port for SSL from 443 to another value (e.g., 1443).
  5. Apply and restart SSRS.
  6. If Veeam installed SSRS for its own reporting (unlikely but possible), consider removing SSRS if not used.