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Which photos application do you use? Have you opened Photos and migrated from iPhoto?
What version of iMovie are you using? You can check in the iMovie menu, About iMovie.
Thanks in advance.
Please close all open applications, make sure only the web browser for this conversation shows as open on the Dock.
Next clear the Cache.
Click Finder, then click the Go menu at the top of the screen.
Click "Go To Folder" and type "~/Library/Caches/" without quotes.
Next click the Edit menu at the top and click Select All, then click the File menu and click Move To Trash.
Next restart your Mac, open iMovie, and check if your pictures appear.
If not get back to me for the next step. Thank you.
The next step could be to rebuild the iPhoto Library, but it is being phased out so it's recommended to migrate to the newer Photos application.
The process is automatic, you just open Photos in the Applications folder and the rest is automatic.
If you really must stay using iPhoto then we can try the full list of things in this article:
OS X: If you can‘t see iPhoto images in other apps
It's ok, no problem.
One question, have you opened iPhoto and verified all your photos appear there?
Ok. Then the issue is communication between iPhoto and iMovie. That's usually done with cache files, but also the iPhoto Library files. If removing the caches doesn't work I would prefer if you migrated to the replacement for iPhoto which is now Photos. If you don't want to do that, or that doesn't work, we can rebuild the library files.
Ok. That's an automatic process, just open Photos and the rest is automatic. How long it takes depends on how many photos are in iPhoto. If the issue is not resolved then we can rebuild the Photos library files.
Ok, please close iMovie again, then go to Applications and open Photos and complete the migration.
To get to Applications open a Finder window.
If it's not on the left in the sidebar, click the Go menu again and click it there.
Once in Applications scroll down to Photos and open it.
When it has migrated and opened Photos, re-open iMovie and check if you can see your photo library.
Ok, when you open Photos, if it does nothing but all your pictures are in it, you've already migrated.
Let me know what happens when you open Photos.
Ok, please close Photos, iMovie, and anything else that is open. Leave just this web browser open.
Press Option-Command and double-click the Photos icon in the Applications folder in Finder.
This opens the Repair window. Clicking Repair rebuilds the Photo library files.
When it completes open iMovie. Let me know what happens.
Just to check. When you say the pictures are not appearing in iMovie, are they pictures you've added to existing projects, or the pictures browser in iMovie?
Can you create a new project, and check if you can browse the pictures from Photos to add to a new project?
Ok. Can you click the Media tab on the right, to see if your photos are listed?
Ok. Can you click the Apple menu and click Software Update. Are there any updates available?
There are some files we need to remove next to try to get them to appear, from the article I linked earlier:https://support.apple.com/HT203149
Please bear with for a bit more, I'm fairly confident we can resolve this.
Please close any open applications, leave just the web browser with this conversation.
Then click Finder, click the Go menu, and click Go To Folder.
Type: ~/Library/Preferences/ and click Go.
Locate the com.apple.iApps preference file and move it to the Trash.
Now open iMovie and check if you can access your pictures in a new project from the media tab.
Let me know how that goes. Thanks.
Did that not work?
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