File does not have an app associated with it. What do I do?

You’ve downloaded a file from a website, clicked on it and absolutely naff all has happened, except an annoying little pop-up message has appeared. “The file does not have an app associated with it for performing this action. Please install an app or, if one is already installed, create an association in the Default Apps Settings page”.

It’s one of those error messages that is about as much help as a dead wasp floating in your wine glass. “Please install an app”? Which one?

How to find what apps open the file

The first thing you need to do is work out what type of file you’re trying to open. Right-click on the file and select Properties. In the window that appears, you should see Type of file listed, along with a three- or four-letter filename type (such as .odt or .indd).

Now, the easiest thing to do is Google that file type. In the examples above, for instance, you’d soon find out that .odt is a text document that can be opened by free word processing packages such as LibreOffice, while .indd is an Adobe InDesign file that must be opened with that particular piece of software. 

If a quick Google search doesn’t help, the excellent fileinfo.com should help identify what the file is.

Missing file associations

This message can also appear after you’ve updated a piece of software to a new version, and all its file associations have been lost. Consequently, when you go to open a certain file type – a spreadsheet, say, or a certain type of image file created in Photoshop – Windows can’t remember which software to open it with.

To overcome this problem, you need to reintroduce Windows to the software in question. Normally, the easiest way to do this is to right-click on the file and choose Open With. A window will appear that allows you to select which app to open the file with. If the app you want isn’t listed, select Look For Another App On This PC and then navigate to the app in question from the Programs folder that will open.

If that doesn’t work, type “default” into the Windows search bar and open the Default Apps setting. Now, click on Choose Default Application By File Type. Down the left of the screen you’ll find a huge long list of file types. Find the one you want, then click Choose a Default next to it. Select the software you want to use for that particular type of file.