Sitecore tracker and sessions errors

The following errors were appearing inside the Sitecore logs:

ERROR Cannot create tracker.
WARN [WFFM] CurrentSession is not initialized
ERROR SessionEndPipeline failed.

These errors relate to the hostname of the site being set incorrectly.

In the Sitecore.config file under the sites node there will be an entry for your Sitecore site. Ensure that the targetHostName value is set to that of your site and that this is also the value that is entered in the hosts file of the server (C:\Windows\System32\drivers\etc).