'You can't open the application "iTunes" because it is being updated.'

Good afternoon brian hardy1,

Welcome to the Apple Support Communities!

I understand you are getting an error message "You can't open the application iTunes because it is being updated." after trying to download the latest version of iTunes on your wife's computer. Is your Time Machine backup recent? If not, please back up before proceeding. Back up your Mac with Time Machine

Based on what you have already tried, I would suggest the following steps:

1. Shut down your computer, disconnect all peripherals, and then start your computer in safe mode. Use safe mode to isolate issues with your Mac
2. Open Activity Monitor and see if iTunes or an installer application is running or updating. Quit the process in Activity Monitor. How to use Activity Monitor on your Mac
3. Open the Applications folder in Finder and drag the iTunes application to the Trash. (This will affect the application only, not the iTunes library).
4. Download a fresh copy of the iTunes application. Download 12.8.2 for Mac
5. Restart the computer and launch iTunes.

Please reply to this thread if the issue persists after trying the steps above, and I'll do my best to help you with this!

Take care.

Hi brian hardy1,

Thanks for letting us know your issue was resolved after downloading iTunes again.

It's really important that you have a copy of your iTunes library. You can do this by dragging a copy of the Music folder to an external drive formatted for Mac OS Extended. You can access the individual music files this way.

But you will also want to get your Time Machine application working to back up your entire computer.

Back up your Mac with Time Machine

Happy Holidays!