'Address Family Not Supported by Protocol Family; Connect' Error

Problem

I have experienced the following error: "Address Family Not Supported by Protocol Family; Connect". How do I solve it?

Solution

This seems to be an IPv6 connectivity problem. By default, the Java runtime used by Oxygen XML Editor plugin prefers to create connections via IPv6, if the support is available. However, even though it is available in appearance, IPv6 sometimes happens to be configured incorrectly on some systems.

A quick fix for this problem is to set the java.net.preferIPv4Stack Java property to true (java.net.preferIPv4Stack=true), by following this procedure:

1. Create a file named custom_commons.vmoptions and add on a single line -Djava.net.preferIPv4Stack=true. Then save the file and copy it to the Oxygen XML Editor plugin installation folder (may need admin access).
2. Restart Oxygen XML Editor plugin.
3. Make sure the procedure was successful by going to Help ⇒ About ⇒ System properties and check that the value of the java.net.preferIPv4Stack property is true.