I thought I would write a quick post on this error, it is very simple to fix. If you receive the following error when importing a Cacti Template:
Error: XML: Hash version does not exist
This simply means the template was generated on a version of Cacti newer than the one you are importing to. Don’t despair, there are simple upgrade instructions on the cacti website.
Just make sure you make a full backup of your database and Cacti webfiles before attempting the upgrade (As a cautionary tale, if you installed cacti from a package you should first check to see if an updated package is available. Package installs can sometimes put the different files required in different places)