Lost all my photos in a guest account after Mavericks upgrade!! Retrievable?

As you have discovered, the guest account doesn't save files, which is how it is designed to work. To make the library accessible from the guest account, you can move the library to the hard drive level User/Shared folder (see next post), which will make it accessible by all accounts. You will then need to tell iPhoto where to look for the library.

From iPhoto help.

Move your iPhoto library to a new location

You can move your entire iPhoto library to a different computer, a hard disk, or another location on your computer.

Important: Before you move your iPhoto library, it’s a good idea to back it up to a DVD or external hard disk.

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Move your iPhoto library

If you’ve created multiple photo libraries, be sure to move only the library currently displayed when iPhoto is open. To move a different library, you first need to switch to it.

Quit iPhoto.

In the Finder, choose your home folder (it’s usually named after you).

Open the Pictures folder (in the home folder) to locate the iPhoto Library file.

1. Drag the iPhoto Library file to a new location on your computer.
2. Open iPhoto.
3. In the window that appears, select the library you want, and then click Choose.

sorry boss😉, its impossible to recover data lost due to login outa the guest account. (its a guest account) meant for temporary files, never use it for any important documents: your neighbours will here you scream in disapointment. trust me i have been down that road😀

Your hard drive in probably named Macintosh.

Do you have a backup you might be able to restore the photos from?

You can try a data recovery program, but you still may not be able to recover them.

Data Recovery – Disk Drill

Data Recovery – Data Rescue

Data Recovery – File Salvage

Data Recovery – Stellar Phoenix

Data Recovery - uFlysoft

i dont think it's the upgrade that messed up ur photos. the guest account only stores stuff temporarily so that when logged out of it, all that data is automatically deleted.😉

your user name is trouble. dont get into more trouble😀