Trying to run app opens DMG file

J1-Helena wrote:

Thanks, but when I double click the DMG, a window opens and states that "The settings pane you are installing is already installed. Do you want to replace the existing settings pane?" I click cancel, as I don't want to lose my settings, and then the app appears. A disk icon also appears on the desktop with the app's name. Should I choose to replace the settings pane?

That means you've already installed the item in Settings. To access it, you go to Settings, not the Application folder. You will never see settings in the Applications folder.

Customize your Mac with System Settings - Apple Support

The disk icon is the running .dmg file.

Settings panes belong in Settings. Applications belong in the Applications folder. It appears that what you were installing is the settings pane for a mouse. So, it's right where it belongs.

When you click on an installer, it installs things exactly where they are supposed to go. Let them do that. If you are installing an application, you will find generally find it in the Applications folder. If you're installing a settings pane, you'll find it in Settings. If you're installing a browser extension, you'll access it through the browser. On some occasions, the installer will ask you where you want to put something but that's not common. They will generally tell you where the item is being installed.

I strongly recommend that you review the Mac User Guide. It has lots of helpful information, including lots of very basic stuff.

macOS User Guide - Apple Support

Just dragging a .dmg file to Applications doesn't install the app. You need to double-click on it and follow the instructions. It sounds as if you're not completing the installation.

I generally do the installs from the Downloads folder because it's then easy to find the .dmg file and delete it when the installation is completed.

What app? You appear to be installing a settings pane. You leave it exactly where it was installed or it won't work. Settings panes are installed into Settings. You access them by opening Settings and then going to that pane. They do not live in the Applications folder.

Once it is installed and you've checked you can access it through Settings, you can delete the .dmg.

J1-Helena wrote:

Thanks again! Yes, the User Guide is a must. I'm coming from a few dozen years with Windows, but Win 11 and MS's intrusiveness was the last straw. BTW, for some reson I couldn't post on my Mac, as I kept getting a message that my post couldn't be saved and telling me to try again later. I had to post from Windows!

That sounds like a big adjustment! But, if you keep at it, you'll get it. Come back any time and ask questions.

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