This issue is most commonly caused when you attempt to install your Joomla51 template package directly to Joomla. Your template comes with a number of different files including template install files for different Joomla versions, modules, guides etc. We have therefore zipped all these files into one package so you can retrieve all files associated with your template in one single download. 

Before you install your template you must first upzip your download in to its separate files and folders. You will then find the install file for your template in the corresponding folder to your Joomla version (eg. j51_yourtemplate.zip).