Backing up your library
It is important to back up your Zotero library regularly. You can save the entire Zotero folder to the cloud or to an external device such as a USB. Note: Avoid saving your original library in a cloud service, otherwise Zotero will not work properly.
Find the folder by clicking on Edit (Windows) / Zotero (Mac) → Settings → Advanced. In the section Files and Folders, the button Show Data Directory allows you to find the folder on your computer. You can save the folder in any location you prefer.
Read more on how to back up or restore your Zotero library.