Hi Julia,
That error message (103) means, the downloaded package could not be installed. That can have two reasons:
- Either it could not be installed, because your user library is corrupted or cannot be written to,
- or the downloaded package could not be opened, because it is corrupted.
When you are running the update, are you signed in as an administrator from an administrator account, or as a regular user? Make sure, you install from an account, that will give you administrator priveleges.
Just try again to install, when your network connection is stable and make sure, that your mac is not falling asleep, while downloading, to ensure that the download will not be interrupted.
You can reinstall your GarageBand from the iTunes Store, if need be. To be able to reinstall, you have to move the garageBand app to the Trash, but do not empty it. Then sign into the AppStore with your AppleID and download again.
This article explains how to reinstall iLife again: Accept iLife: OS X: About OS X Recovery
scroll down to the paragraph in the middle: Restoring iLife applications after Internet Restore of OS X Lion or OS X Mountain Lion
Regards
Léonie
. I also do not have iLife (I've heard about that from various people).
BTW: you have iLife.
All new Macs come with iLife - it is the suite of the programs iPhoto, GarageBand, iMovie.