EagleFiler libraries can be encrypted or unencrypted, but you have to decide which when you create the library. To encrypt an existing library:

1. Close the old library in EagleFiler.
2. Choose File ‣ New Library… and create a new encrypted library.
3. Close the new library in EagleFiler.
4. Click on the library’s white disk image icon in the Devices section of the Finder’s source list.
5. Move everything (Files, NewLibrary.eflibrary, Notes, To Import (NewLibrary)) to the trash.
6. In the Finder, drag the contents of the old library’s library folder into the new library’s disk image (in Devices).
7. Drag the old library’s library folder to the trash and empty it.
8. The old library and any temporary files that were used to create it are now deleted but may remain on your hard drive, unencrypted. To securely erase them, open Disk Utility, select the drive that stored the old library, choose the Erase tab, and click Erase Free Space…. You can then do a 7-pass erase to remove any traces of the deleted files.