Q. All my PDFs or Groups in EndNote are gone. How do I fix this?
If the PDFs you’ve attached to your references suddenly become inaccessible or your Groups disappear, it’s likely that the .Data folder associated with your EndNote library is no longer in the same folder or directory as the EndNote library file (extension .enl). You need to find this .Data folder and move it back to the same location as your EndNote library file. Once you do this, the links to the PDFs/your Groups should be restored.
If you’ve synced your library with EndNote Online, you may be able to recover your PDFs/Groups that way too. Select the Sync icon in EndNote to try.