Some of us may have not updated Aperture since Yosemite or skipped the Yosemite update, this article is for you.
If you upgraded to El Capitan or Yosemite and still has Aperture of version earlier than 3.6. You will realise that it is not possible to open the app and attempting to update result in a failure. Fear not, MacRiot has outlined the steps to updating Aperture and I will like to share it with everyone here.
Step 1) Drag Aperture to Trash but DO NOT empty the Trash
Step 2) Launch the App Store, Go to the Purchase tab and look for Aperture and click install
Step 3) After installing run Aperture to check if it is working fine. If it is fine, it is now safe to empty the Trash
Credit to MacRiot
TechCentral 
Thank you so much – panic over!
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Wow, worked great!
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Thanks – that seems to have worked
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I have Aperture 3.4.5 and somehow it is not in the “Purchased” section of my app store. It is in my application folder and on my dock and I did buy it… but I tried to do what the thread suggested and came to realize there was no way for me to re-download. Any help would be amazing.
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same problem here. not in the purchased tab.
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I had just checked using app store link however it is indicated that it is not available (https://itunes.apple.com/us/app/aperture/id408981426?mt=12).
I guess Apple had removed it from the app store? However there was an article from Apple dated May 2016 which give a similar step to installing Aperture (https://support.apple.com/en-sg/HT200097). You might want to contact apple for support since you purchased it previously.
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any more suggestions? need a little help from my friends.
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I had just checked using app store link however it is indicated that it is not available (https://itunes.apple.com/us/app/aperture/id408981426?mt=12).
I guess Apple had removed it from the app store? However there was an article from Apple dated May 2016 which give a similar step to installing Aperture (https://support.apple.com/en-sg/HT200097). You might want to contact apple for support since you purchased it previously.
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