This article was previously published under Q310099
Portqry.exe is a command-line utility that you can use to help troubleshoot TCP/IP connectivity issues. Portqry.exe runs on Windows 2000-based computers, on Windows XP-based computers, and on Windows Server 2003-based computers. The utility reports the port status of TCP and UDP ports on a computer that you select.
Note Version 2 of Portqry.exe is now available. The Microsoft Download Center link at the end of this article has been updated to reflect the new version. Version 1.0 of Portqry.exe has been removed from the Microsoft Download Center.
Portqry.exe reports the status of a TCP/IP port in one of the following three ways:
A process is listening on the port on the computer that you selected. Portqry.exe received a response from the port.
No process is listening on the target port on the target system. Portqry.exe received an Internet Control Message Protocol (ICMP) "Destination Unreachable - Port Unreachable" message back from the target UDP port. Or if the target port is a TCP port, Portqry received a TCP acknowledgement packet with the Reset flag set.
The port on the computer that you selected is being filtered. Portqry.exe did not receive a response from the port. A process may or may not be listening on the port. By default, TCP ports are queried three times, and UDP ports are queried one time before a report indicates that the port is filtered.
Portqry.exe can query a single port, an ordered list of ports, or a sequential range of ports.
The following command tries to resolve "reskit.com" to an IP address and then queries TCP port 25 on the corresponding host:
portqry -n reskit.com -p tcp -e 25
The following command tries to resolve "169.254.0.11" to a host name and then queries TCP ports 143,110, and 25 (in that order) on the host that you selected. This command also creates a log file (Portqry.log) that contains a log of the command that you ran and its output.
The following command tries to resolve my_server to an IP address and then queries the specified range of UDP ports (135-139) in sequential order on the corresponding host. This command also creates a log file (my_server.txt) that contains a log of the command that you ran and its output.
Important The PortQueryUI tool provides a graphical user interface and is available for download. PortQueryUI has several features that can make using PortQry easier. To obtain the PortQueryUI tool, visit the following Microsoft Web site: