If you are not the only person who has access to the computer where you keep your iPhoto library, it might be a good idea to protect it with a password. While setting up one involves a long series of steps, these are pretty straightforward and easy to follow. Setting up a PasswordIn the Disk Copy utility, open the folder where you store your iPhoto library. Create a disk image of the iPhoto library folder by dragging it to the Disk Copy window. A dialogue box with the heading Image Folder pops up. Here you have to navigate to the directory where you wish to temporarily store the newly created disk image. Verify that the name of the disk image is “iPhoto Library”. Set Image Format to read/write and Encryption AES-128. A dialogue box asking for a password appears. Type your password but be sure not to simulation software store it in your keychain. Close Disk Copy utility. Select a place where you want to keep your iPhoto library. Create a folder for it and provide an appropriate name. Drag the disk image into the folder, and delete the original iPhoto library folder. This is the folder that was first dragged to the Disk Copy window. Double-click the new disk image and enter your password to mount it, then open iPhoto. The application will not be able to find your library, returning a Library Not Found error. The reason is that the original library was deleted. What you need to do is to choose Find Library and go to the mounted disk image. You can eject the mounted disk image if you wish to protect your pictures. iPhoto will always return the message that it cannot find your library unless the disk image is mounted.