The Windows OS's come with a number of tools built in that can assist you in troubleshooting network / tcp connections from a Windows PC. These commands are found in the DOS terminal which can be opened by selecting "Command Prompt" from Programs menu of the Start menu. The commands include; arp, hostname, ipconfig, nbtstat, netstat, ping, route, tracert. For instance:To get the IP Address, Subnet Mask and Default Gateway of a computer enter the command: ipconfig
To test if packets are reliability being sent and received between 2 computers, use ping. Type ping followed by a space and the ip address:
ping xxx.xxx.xxx.xxx
Another way of testing the path (route) between 2 computers is to use tracert. Just type:
tracert xxx.xxx.xxx.xxx
To learn details such as what ports are being used on this computer, use the command netstat.

For More information:
There are 2 sources of information on these commands. In DOS it is sometimes possible to get parameters for the commands by either:
- typing the command with no parameters
- typing the command with a ? parameter
Microsoft's web site is an excellent source of information on these commands and troubleshooting information. To search for technical support/troubleshooting information go to: http://support.microsoft.com/support/search/c.asp? or select the category "Support & the Knowledge Base" in Microsoft's general web site search.

Helpful Hints:
Some of the commands return more information than can be displayed in 1 screen. DOS provides a command more that displays only one screen at a time allowing the user to view the contents before displaying more information. To use ' | more' at the end of the line. For example: C:\>netstat -se | more
It is also possible to save the output to a text file by using the '>' character. For example to create a file called 'results.txt': C:\>netstat -se > results.txt
To view a text file use the EDIT command. For example: C:\>edit results.txt
Note: The MORE command and '>' do not work with all commands. Also, Windows NT has all of these commands but Windows 95 and 98 only have some of these commands.