To check if a specific port is open on a server, you need to run a command in your system console as not all hosting services may support it. This is especially useful when verifying if a port is open before integrating it with your email service or troubleshooting SMTP configuration issues.
Use the following tabs to view instructions for Windows, Linux, and MacOS:
To check if an SMTP port is open on a server using Windows:
- To open the Run dialog box, press Windows+R keys together.
- Type
cmdand click OK.
💡 Good to knowIf administrative privileges are required, press Ctrl+Shift+Enter to run the command prompt as an administrator. - In the Command Prompt window, type the following command:
netstat -an | find "<port>" - Replace
<port>with the port number you want to check. For example, to check if port 25 is open, type:netstat -an | find "25"
If the specified port appears in the results, it means the port is open and in use.
To check if an SMTP port is open on a server using Linux:
- To open the terminal window, press Ctrl+Alt+T keys together.
- In the terminal window, type the following command:
lsof -i:<port> - Replace
<port>with the port number you want to check. For example, to check if port 25 is open, type:lsof -i:25
If you see a list of processes using the specified port, it means the port is open and in use.
To check if an SMTP port is open on a server using MacOS:
- To open Spotlight Search, press the F4 key.
- To open the terminal window, type
terminalin the search field and press Enter. - In the terminal window, type the following command:
lsof -i:<port> - Replace
<port>with the port number you want to check. For example, to check if port 25 is open, type:lsof -i:25
If you see a list of processes using the specified port, it means the port is open and in use.
If no results appear, the port might be closed or blocked by a firewall. In this case, we recommend you try using one of our other SMTP ports or contact our support team with a screenshot of the message you got.
⏩ What's next?
- Which SMTP port should I use? (Port 587, 465, or 2525)
- Troubleshooting issues with Brevo SMTP
- Send transactional emails using Brevo SMTP
🤔 Have a question?
If you have a question, feel free to contact our support team by creating a ticket from your account. If you don't have an account yet, you can contact us here.
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