Only one usage of each socket address (protocol/network address/port) is normally permitted.

Question

I'm using .NET 6 Web API with COSMOSDB and

facing issue like Only one usage of each socket address (protocol/network address/port) is normally permitted. when requesting many more APIs calls

Answer 1

It is a complete disaster that people looking for help inevitably waste their time and money on reading such a useless and rubbish computer-generated pointless and misleading crap of text. Facts: 1. That error is thrown when you try to LISTEN on an endpoint, that is already acquired to listening by some other software running on local computer. It has nothing to do with suggested "too many requests". 2. That error started to occur on Windows 11 even if the above condition is not actually met. Why? I don't know. I'm searching for a correct answer, but to the moment had no luck and found only misleading AI - suggestion. Just close this useles portal. stackoverflow and others do their job much better.

Answer 2

The error message "Only one usage of each socket address (protocol/network address/port) is normally permitted" typically occurs when there are too many connections being made to a single endpoint. This can happen when there are too many requests being made to Azure Cosmos DB from your .NET 6 Web API. One solution is to increase the number of available ports on your machine. Another solution is to optimize your code to use fewer connections to Azure Cosmos DB. You can also consider using connection pooling to reuse existing connections instead of creating new ones for each request.

---

References:

• Diagnose and troubleshoot issues when using Azure Cosmos DB .NET SDK
• Performance tips for Azure Cosmos DB and .NET

Answer 3

1. Identify the port in use and find the associated PID:

netstat -ano | findstr :1041

Output Example:

  TCP    0.0.0.0:1041           0.0.0.0:0              LISTENING       14392

The PID in this case is 14392.

---

2. Trace the parent process of the PID:

wmic process get processid,parentprocessid | findstr/i 14392

Output Example:

14392            9584

Here, 9584 is the parent process of 14392.

---

3. Check for child processes under this parent process:

wmic process where (ParentProcessId=9584) get Caption,ProcessId

Output Example:

Caption      ProcessId

This revealed a conhost.exe process with PID 38776.

---

4. Terminate the identified process:

taskkill /f /pid 38776

Output Example:

SUCCESS: The process with PID 38776 has been terminated.

After this, the port was released, and I could restart the application without rebooting the system.

---

Key Insight:

In some cases, the process occupying the port might not appear directly in tasklist or through taskkill with the initial PID. However, by tracing the parent process and terminating its child processes (like conhost.exe), the issue can be resolved without restarting Windows.

I hope this helps someone else facing a similar ghost process issue!