
Kext or Kernel Extension files are the drivers for macOS. To check whether kext files are causing the error, move all of them out of your Extensions folder before rebooting your Mac. To move your kext files, follow the steps below: Boot your Mac into Safe Mode by holding down the Shift key until you see the Apple logo.
Sometimes, when you use iPhoto to open a photo library, you may see an error that says ‘This photo library is locked, on a locked disk or you do not have permissions to make changes’. What are the reasons for the error and how can you resolve it? Let us understand more in this article.
Case 1: Make sure iPhoto is being accessed from only one machine
Please note that the iPhoto library can be accessed from only one iPhoto at a time. So, if you are accessing the library that is already open on another machine (using file sharing or any such feature) you may receive the error. In that case, close the iPhoto on the machine that has it open and try re-opening it on your machine.
Case 2: Obtain read and write permissions
To be able to open the iPhoto library, it requires that you have both read and write permissions. Even if you don’t intend to make changes to the library, you still need to have write permissions just to open the library and view images.
This will help you obtain all read-write permissions to the drive on which iPhoto library is present. Now you should be able to open the library without any issues.

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Case 3: Repair iPhoto library
If the above methods don’t help, there may be corruption issues within your iPhoto library. To repair such issues, use the built in Repair library feature as explained in the steps below.
If Repair library doesn’t fix the issue, you can also use ‘Rebuild the iPhoto library database’ feature which will allow you to rebuild the library. This can resolve most problems, but before you attempt this step, make sure to have a backup of your photos just in case anything happens during the process.

However if you have lost photos after repairing or rebuilding library, and no backup is available, you can use Remo Recover to recover lost photos from iPhoto library. A trial version of the software is available for free, be sure to try it out today!