A. I don't really know ! - I just speculate ! (so that this is 100% clear)
B. iMovie - on starting up - locates the other programs libraries as iPhoto, GarageBand etc (all in iLife suite)
If they have been changed to Libraries outside the Main Start-Up Hard Disk === iMovie gets LOST !
My iPhoto Library is really swelling up - So I'm in the need to re-locate it to an external drive - BUT then iMovie can not reach it any more.
I've not found any solution to this.
So Main advice is to - NOT set iPhoto or the other parts to address any other external Libraries !
the iMovie Event's and iMovie Project's - can be moved to an external storage (BUT NOT via FINDER - only from within iMovie - else links breaks)
As I see it - there is only way's around this by - on the Main Start-Up Hard Disk - Create a folder that You fill with the Photos and Audio You need for Your Movie - AND KEEP THIS TILL Movie is done AND Distributed (via DVD or YouTube or whatever) - as they are needed all the time till You are really finished ! there are NO safe copies in iMovie or iDVD or elsewhere !
Yours (really trying to be of help - fingers cross that I made it all the way) Bengt W
This solved my question by Old Toad on Aug 1, 2013 1:43 PM
Try the following:
Delete the following two preference files from your Home/Library/Preferences folder:
Launch iPhoto and then iMovie and check the Media Browser again.
NOTE: In Lion and Mountain Lion the Home/Library folder is now invisible. To make it permanently visible enter the following in the Terminal application window: chflags nohidden ~/Library and press the Return key - 10.7: Un-hide the User Library folder.
First, I closed all Apps and then I had to open terminal and enter the text in red above to find the Library in HOME.
Then, I ONLY deleted com.apple.iApps.plist.
Finally, I opened iPhoto, then iTunes, then GarageBand, and lastly iMovie.
iMovie populated photos, music, exactly as it should have. And GarageBand populated my itunes music!
Thanks to all who took the time to offer a solution!