Port 443 For Veeam Backup Replication Is Occupied By Another Application Link — Required

There are two main ways to resolve this: change the port for the conflicting application (Recommended) or configure Veeam to use a different port.

tasklist /svc /FI "PID eq 1234"

Or using PowerShell:

Get-Process -Id (Get-NetTCPConnection -LocalPort 443).OwningProcess

Important: Changing Veeam’s port impacts: There are two main ways to resolve this:

After freeing port 443:

netstat -ano | findstr :443

Example output:

TCP    0.0.0.0:443           0.0.0.0:0              LISTENING       1234

The number 1234 is the Process ID (PID).

If the process is System (PID 4), the port is being reserved by the HTTP Kernel Driver (HTTP.SYS). You cannot kill PID 4. Instead, you must remove the URL reservation. There are two main ways to resolve this:

Run this command in an elevated CMD or PowerShell:

netsh http show urlacl | findstr :443

This will list all URL reservations. Look for something like:
http://+:443/ or https://+:443/ reserved for a specific user or service group (e.g., NT SERVICE\SSRS). There are two main ways to resolve this:

To delete the reservation:

netsh http delete urlacl url=http://+:443/
netsh http delete urlacl url=https://+:443/

After deletion, restart the Veeam services or the installer.