For a change from the usual Windows stuff here, I bring a MacOS diagnostics article. In this case a brand new shiny MacBook Air Laptop straight out of the box was unable to install the additional sound library via Apple Software Update. The 1.2 GB download had failed part of the way initially when the internet connection dropped. Ever after that it would re-try to download the 1.2 GB, in fact it would even progress to 1.2 GB then right at the very end fail … for reasons “Unable to verify the download, please try update again” After 3 times trying again, including from different internet connections it was becoming a bit tiresome.
One thing I noticed was the note at the bottom of software updates: “GarageBand Instruments and Apple Loops: Partially downloaded (13%)”
So I thought maybe clearing this would resolve the problem. I wasn’t sure where this download was cached, but initially tried clearing the following folders:
However the partial downloaded remains. Searching the internets I found many people with same issue, but hadn’t seen any really good solution, most involved re-installing the entire OS, or getting the iLife DVD – but in the case of the Air no DVD drive, and the software came pre-installed.
So to find where the update was getting cached I opened up a terminal and ran the following command:
sudo fs_usage | grep -i “update”
fs_usage is a file system activity monitor built into MacOS, it allows us to see various file activity, what file is accessed, from what process, and what type of operation is being performed on file (i.e. read/write) As there can be a lot of irrelevant data shown I used grep with the -i option (case insensitive filter) to only show data with the word “update”
What interested me was the /private/var/folders/g1/<gibberish>/C/com.apple.SoftwareUpdate/content/downloads folder.
To browse to this folder in Finder I selected menu option Go | Go To Folder… then typed /private/var/folders and selected Go￼
I then clicked through the folders until I got to the com.apple.SoftwareUpdate/content/downloads folder. I then dragged all the folders there into the Trash Can. (or Garbage / Recycle Bin as you like…)
I then closed Software Updates, and re-opened Software Updates. OK great – the “13% already downloaded” was no longer there.
I installed the item…and sure enough it finally succeeded!