My sons each have a Mini on their desk, and I usually update them simultaneously. I am the only admin, so I have no idea what has happened here. One computer is updating now as expected. The one one I'm typing on now, does not show the App Store in the Control Panel and the App Store window looks more like Apple Car Play than I'm used to. How did this happen and how can I change it back?
Thanks
The screenshot you show is from a Mac running macOS Mojave, and yes the App Store is different on Macs running this OS.
The other Mac must be running an older macOS.
Click on the Apple top left of the screen and then click on About This Mac, the panel that pops up will tell you information about the Mac and also which OS and version number.
Apple has revised the user interface of the Mac App Store in Mojave. Not something you can revert of otherwise fix.
app store looks different
