Plugin installations usually go without problems if you follow the general Redmine plugin installation steps or specifically written instructions from the plugin's docs. But sometimes, a plugin won't work with your Redmine installation, or even worse, it breaks your installation. This recipe deals with some common plugin installation problems.
It is not good practice to test plugins in production environment. Redmine lets you use console value
RAILS_ENV=development for test or development purposes. But, it is always recommended to create a full backup of your system prior to plugin installation.
Make sure that the plugin you are installing is compatible with your version of Redmine.