PortCheck lets you check if a remote device answers on a certain TCP port via a straightforward Command Line tool.

Versatile Tool
PortCheck is a versatile tool that allows users to set the timeout for requests and customize descriptions for each port. It ensures comprehensive logging of all findings and actions performed. Additionally, it provides a range of advanced parameters. For example, users can opt for continuous monitoring with discreet alarm notifications to receive port availability information promptly. Moreover, PortCheck allows users to configure specific time intervals between consecutive checks, enhancing control and customization options. PortCheck can also be integrated with batch files if required.

Usage
Run PortCheck.exe from the Command Line to begin to test a TCP port as follows: PortCheck.exe

PortCheck Response
PortCheck responds to the form of an ERRORLEVEL, which is based on the received answer. If there is no response, the port is considered free, resulting in an ERRORLEVEL of 0. Conversely, the port is in use if a response is received, resulting in an ERRORLEVEL of 1. Additionally, the application offers supplementary options to display opened ports exclusively and customize the color codes used.

PortCheck is an essential tool for system and network administrators. It sends requests to check for responses on specific ports, providing response times and color-coded outputs. It can simultaneously verify multiple devices and ports and promptly notify you of any changes in port status, making it a valuable utility in any admins toolbox.

Below is a list of often-used TCP ports; syntax examples are also available on the author's site.

21 - FTP
22 - SSH
23 - Telnet
25 - SMTP
80 - HTTP
110 - POP3
135 - DCE / WMI
139 - NetBIOS
143 - IMAP4
443 - HTTPS
445 - SMB
1433 - MS SQL
1494 - ICA (Citrix)
1521 - Oracle
3389 - RDP
5060 - SIP
8080 - HTTP alternative
8443 - HTTPS alternative

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