Plugins can be used to update and delete information from your project and from your hard disks. It is important therefore to get in to the habit of developing plugins using a copy of your project, or using the sample project provided with Family Historian. That way should your plugin go wrong (if, for example, it did what you told it to do and not what you wanted it to do) you will not have lost any information.
To copy an existing project, click the button on the Project Window, select 'Copy Project' and provide the copy with a new name. See Copy Project in the main help.
It is a good idea to export your plugins regularly to an external folder, so that if you ever make a mistake and delete something you shouldn't have, you can always restore (re-import) an earlier version. Plugins can be exported by clicking the button in the Plugins Window, which is accessible from the Tools menu. You will need to click the button to see the button.
Note: Advanced users who write a large number of plugins may find it more convenient to backup plugin files, by copying them directly from the ProgramData folder area.