Fatal error: Call to undefined method JXMLElement::getElementByPath() in ... on line ... - the cause of this Joomla Administration Message

If your server reports the "Call to undefined method JXMLElement::getElementByPath() in ... on line ..." error during a Joomla Extension installation, in most cases the cause of this message is, that your extension is not compatible to your Joomla version.

Than it's necessary, that you download the right version of your extension on the developers site and install it at Joomla. This usually happens, if you use a version of Joomla, for which there is no further development of your extension.

Or, you use a deprecated version of Joomla and your extension wasn't developed for that. In this case, you can solve the error, if you update your Joomla version.