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User profile for user: Kris Reid
Kris Reid Author
User level: Level 1
9 points

iMovie running incredibly slow - slows down my MacBook Pro

Hi all,


I've encountered a problem with iMovie. It is running extremely slow and in turn slows down my MacBook Pro. I don't know what the issue is but I suspect it is some sort of background task that I am unaware of. I can't use iMove at all now. Super frustrating. Anyone have any ideas?


Thanks,


Kris

MacBook Pro 13", macOS 10.14

Posted on Mar 9, 2019 6:03 AM

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User profile for user: Rich839
Rich839
User level: Level 8
47,250 points

Posted on Mar 9, 2019 8:05 AM

Hi, Kris,


Make sure that you have sufficient free space for iMovie to operate -- somewhere around 20 GB should be enough. Check the Activity Monitor app to see that there aren't other CPU intensive programs running in the background. Sometimes a very large iMovie library can slow down the app.


Some things you can try:


  1. Delete preferences by restarting your computer and opening iMovie while holding down the Option and Command keys and selecting to delete preferences in the box that appears. iMovie will open in a new library. Reopen your old library to get back to your projects. See if that cures the problem.
  2. Open iMovie in a new library by opening iMovie while holding down the Option key, and selecting to create a new library in the box that appears. Then try running iMovie.
  3. Boot up in Safe Mode (see Finder Help menu for directions), and then, after everything loads, immediately shut down and reboot in normal mode.


If still no luck, possibly you need to reset your System Management Controllor. It is not a very common problem, but one of the symptoms is the CPU running slowly. For more information, here's a link that discusses the issue:


https://support.apple.com/en-us/HT201295


-- Rich



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User profile for user: Rich839
Rich839
User level: Level 8
47,250 points

Mar 9, 2019 8:05 AM in response to Kris Reid

Hi, Kris,


Make sure that you have sufficient free space for iMovie to operate -- somewhere around 20 GB should be enough. Check the Activity Monitor app to see that there aren't other CPU intensive programs running in the background. Sometimes a very large iMovie library can slow down the app.


Some things you can try:


  1. Delete preferences by restarting your computer and opening iMovie while holding down the Option and Command keys and selecting to delete preferences in the box that appears. iMovie will open in a new library. Reopen your old library to get back to your projects. See if that cures the problem.
  2. Open iMovie in a new library by opening iMovie while holding down the Option key, and selecting to create a new library in the box that appears. Then try running iMovie.
  3. Boot up in Safe Mode (see Finder Help menu for directions), and then, after everything loads, immediately shut down and reboot in normal mode.


If still no luck, possibly you need to reset your System Management Controllor. It is not a very common problem, but one of the symptoms is the CPU running slowly. For more information, here's a link that discusses the issue:


https://support.apple.com/en-us/HT201295


-- Rich



Reply

iMovie running incredibly slow - slows down my MacBook Pro

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