[Solved] JInstaller: :Install: Cannot find XML setup file - Error in the installation of a Joomla Extension- options to solve this problem

If your Joomla Administration spits out the "JInstaller: :Install: Cannot find XML setup file -  error" in the installation of a Joomla Extension, there are following two possibilities to solve it.

First Option:

Check, if the installation package includes a xml setup file. A extension package without a xml setup file does not work. In this case, you must download a package of your extension, which includes a xml setup file or contact the author of your extension.

Second Option:

Sometimes it's important, that you unzip the installation package local before you install it at Joomla. Some authors provide their extension in a package with other files. The real installation package is only one of the files in your package. You can recognize it, if your package was described previously with the term "unzip first", but this is not always the case.