imovie storage

Hi,

Select the library's icon and do an Edit/Copy and then Edit/Paste it into the external drive. When you verify that everything is working on the external drive, you can delete the library from your internal drive. Alternatively, you can chose to drag the library to the external drive, but I believe that doing the Edit/Copy, Edit/Paste procedure is safer.

Before moving the library make sure that your external drive is formatted Mac OS Extended (Journaled) or APFS. If you need to reformat the drive be aware that reformatting deletes all data on the drive. Further, in the Get Info box of the external drive make sure that the box at the bottom is checked that says "Ignore ownership on this volume."

Also, before moving the library open iMovie and select the library's name in the sidebar. Then do Edit/Consolidate Library Media. That will insure that the library brings all of its media with it.

Here's an Apple link that describes how to move an iMovie library:

Move your iMovie for Mac library – Apple Support (AU)

-- Rich