Whenever you double click on any file on your Mac within the Finder, the operating system will by default find the most suitable app to open it and reveal its contents. Most of the time everything will work without issues, but there are other times when your Mac will either not use the ideal app to open a file or will simply not be able to find a suitable app at all.
So I would like to make my application default for this file type, so Preview will not open it by default. Some google search has revealed that in Mac OSX there is key like LSIsAppleDefaultForType, that can make app default, but I can't find any option for IOS. I have to set the default telephone app on 10 iMacs and don't want to register 10 iCloud-accounts just to do the facetime login and being able to open the preferences there. That's ridiculous. Installed RCDefaultApp and set the default telephone app there but the phone-icon in contacts application is still greyed-out. Now that you’ve changed the default program for this file, the button for Change All is active. This button will set your Mac to use the selected application to open files of this type.
If you have experienced this issue before and would like to know how to solve it, read along. What causes this issue most of the time is that you might have two or more apps that support the type of file that you want to open.
For Example: Some very frequent culprits of this are archiving apps like Winrar or UnRarX, both of which support very similar file types. Another common occurrence is mix-ups between video players like VLC and Quicktime, with the latter opening files only supported by the former.What you need to do in order to solve this issue is to change the default app for opening certain types of files, or at least choose a different app from the available ones to open a particular file. Follow these steps to learn how to do just that.
Open File with Different Program
Step 1: First, start by locating the file you want to open within the Finder.
Step 2: If you want to open the file with a different app than the one set by default only once, then all you have to do is right-click on the file, click on the Open With option and then select the app you want to use from the list of available programs.
Set Default Program for Specific File Types
Step 1: To set a different default app for all files of a certain type, you can also start by locating a file of that type first and then by right-clicking on it. This time though, locate the Get Info option and click on it.
Step 2: This will display the information panel for that particular file. On it, look for the Open with: section located almost at the bottom of the window. If it is not open, click on the small triangle until the information is displayed just like on the screenshot below.
Step 3: There, you will see a dropdown menu that will display all of the apps that support the file and are capable of opening it. Click on this menu and then select the application that you want to use to open that file type from then on.
If you don’t find the app you are looking for on the list, simply click on Other… to look for one within the Applications folder.
Step 4: Once you select the application you want, click on the Change All… button to apply the changes. Then, confirm your selection on the next window.
Once you are done, just close the information panel and you will be set to go. From now on, every time you open any file of that type, it will open in the new application you selected.
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