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I have a socket app that passes data between 2 processes. It works fine on a number of computers with the 2 processes running on the same computer. A person in my office visited a government office where they made some unknown changes to her laptop so she could get on their network. When she left the app no longer works.

If she tries to telnet to the listener app she can connect if she tries to connect to the computer name or 127.0.0.1, but connecting to localhost doesn't work. Any ideas?

Jake Pearson
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4 Answers4

15

Check the Hosts file, located here: C:\WINDOWS\system32\drivers\etc

This file is what translates localhost to 127.0.0.1

AaronS
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5

Perhaps the localhost mapping in %systemroot%\system32\drivers\etc\hosts is pointing to an IPv6 address and the program does not support IPv6.

Does the entry in the hosts file look like this:

127.0.0.1 localhost

or like this?

::1 localhost

Please go to start, run, and type:

notepad %systemroot%\system32\drivers\etc\hosts

to check.

Brian R. Bondy
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  • This was exactly the issue. My app was skipping over IP6 addresses. We changed the host and it was fixed. Now I have need to change my app. – Jake Pearson Apr 15 '09 at 19:01
2

Check the hosts file?

Wait; do you mean when she telnets to localhost it works, or when she telnets to her IP it works?

overslacked
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0

Just in case this happens to be a *nix system, you can find the host file here:

/etc/hosts

Andrew Hare
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