When you click on a Word document, what happens? Well, if all goes according to plan, Microsoft Word or a Word-compatible program opens and displays your file. The same is true of anything you click on: Windows needs to know what program is associated with that type of file, even if Windows itself is the program.

Usually this works so well that we don’t even have to think about it. But sometimes file associations get changed when we uninstall a program, by malicious software, or simply by mistake. Here’s what to do.

Try the normal way first

The first thing to do is make sure your computer isn’t infected. Be aware that sometimes file associations are changed by malicious software. If this is the case, you need to remove the malware before changing the file associations.

So, assuming your computer is malware-free, make sure you have installed the right program for your file. Usually there is a way from within a program to set it as the default for certain file types. Always try that first.

You can do it from within Windows

If you have the right program and it still doesn’t know it’s the boss of your file, you can follow the instructions here for Windows 7: http://windows.microsoft.com/is-IS/windows7/Change-which-programs-Windows-uses-by-default, here for XP: http://support.microsoft.com/kb/307859 and here for Vista, the forgotten Operating System: http://windows.microsoft.com/en-US/windows-vista/Change-which-programs-Windows-uses-by-default.

Photo: Contributed

Try these utilities instead

If your eyes are already glazing over, don’t worry. There are three little utilities that will do the job in less time than it takes to read all that. Before you use any of these utilities, make sure you’ve created a System Restore point, so if you make a mistake you can reverse the process.

Default Programs Editor, available here: http://defaultprogramseditor.com/, makes it pretty easy to fix, change, and delete file associations in Vista and Windows 7. I have used it many times, but I don’t know if it works with XP and I don’t see anything on the developer’s site that answers that question.

Unassoc.zip is a helpful little utility with a workman-like interface. Its mission in life is to make it easy to unassociate a file type in Win7 or Vista. You get to start over for that file type.

Why would you need to do that? Remember I mentioned that sometimes file associations get changed by mistake? Recently a colleague managed to change all his desktop icons so that they tried to open Firefox regardless of what the icon was supposed to do. A desktop icon is a .lnk file. He used the unnassoc utility to remove the .lnk association, turning all the icons back to normal and restoring the correct behaviour. You can get the utility from The Windows Club website, here: http://www.thewindowsclub.com/how-to-dissociate-file-types-in-windows-7-and-vista.

File Association Fixer, also from The Windows Club, is available here: http://www.thewindowsclub.com/file-association-fixer-for-windows-7-vista-released. It will detect whether you’re running Windows 7 or Vista and offer you the appropriate fixes. I’ve used the first two utilities with much success. I haven’t tried the third. All three utilities are free.

Do you need help with your computer? I'm here to help you and your home or business computer get along!

Cate Eales runs Computer Care Kelowna (http://computercarekelowna.com/) a mobile service helping home users and businesses get along with their computers. To arrange an appointment phone her at 250-764-7043. Cate also welcomes your comments and suggestions. Send email to help@computercarekelowna.com.

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