"The following url is not valid" error message when you try to publish an InfoPath form to a Microsoft SharePoint Server 2010 site

You have a Microsoft SharePoint Server 2010 site that does not have a root site collection. When you try to publish an InfoPath form to this site, InfoPath returns the following error message:
The following url is not valid ...

This problem also occurs when you try to publish the InfoPath form to a site collection other than the root site collection.
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CAUSE
This problem occurs because InfoPath makes a call to determine the version of SharePoint Server that is being run by the server. This call is performed as part of the publishing process, and the call is made to the root site collection. When no root site collection exists, the call cannot to determine the version of SharePoint Server that is being run by the server. Therefore, the publishing process fails.