Q: Updating iphoto and imovie

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It's possible that iPhoto and iMovie are hidden, and that's why you can't update them. First, see if they are hidden, and if they are, unhide the applications > http://support.apple.com/kb/HT4928?viewlocale=en_US&locale=en_US Finally, you will be able to update them to the latest version

To buy a new copy you would have to uninstall the current copy.  You may be able to contact App Store support and find out what account holds the license if you don't delete it though

Please try each of the following steps you haven't already taken, until the issue is resolved. After each step, relaunch the App Store and try again.

1. Follow the instructions in the Apple Support article linked below:

Mac App Store: Cannot update App Store purchases or updates do not seem available

2. If any App Store purchases were made under a different Apple ID, or if the bundled iLife applications were accepted under a different ID, sign in to the App Store with that ID to update.

3. Alternatively, delete the probem applications and re-download them with the ID you're using now. If you haven't already purchased them with that ID, you'll have to do that first, because purchases can't be transferred from one account to another.

4. Select the Purchased tab in the App Store window. If you see an item in the list marked "You have 3 apps to accept," click Accept.

5. Triple-click the line below to select it:

/Library/Caches/com.apple.appstore/adoption.plist

Right-click or control-click the highlighted line and select

Services ▹ Reveal

from the contextual menu. A Finder window may open with a file selected. If it does, delete the selected file. You may be prompted for your login password.

Then repeat step 4.

6. Select

Store ▹ View My Account

from the App Store menu bar, then select View hidden purchases. If you're trying to update any hidden purchases, unhide them.

7. Launch iTunes and select

Store ▹ Authorize This Computer

from the menu bar.

8. If you've moved any App Store apps out of the applications folder, or into a subfolder, put them back. Never move or copy those applications.

9. Contact Account and Billing Support on this page:

Apple - Mac App Store - Contact Support