Helping people with computers... one answer at a time.

Program file extensions can sometimes be in conflict. You can't change the programs, but you can still run them both on your machine with an easy work-around.

Is there a solution to different programs using the same file extensions? In my case specifically, I can't install Apple's QuickTime because it uses a file extension QTX which is also used by Quicken 2011 program. Google searches come up essentially empty. I'm running Windows 7 Pro.

In this excerpt from Answercast #96 I look at some problems that can arise when different programs try and share a file extension - and easy steps that allow you to use both programs.

Program file extensions

The very short answer is "no" - but a part of your question concerns me a little bit. You should be able to install all the programs you want.

In other words - a program should not fail to install because some other program which uses an extension that your first program uses happens to be on the machine. Everything should install just fine.

Default program to open file

The conflict arises when you try and double click on a file to open it. In fact, that's pretty much the only time the conflict really happens.

What you end up with typically is that the last program to be installed is usually the program that then owns that file extension.

Default programs

So for example, in the case of .qtx, if you have Quicken installed and you then install QuickTime - it's very possible that when you double click on a .qtx file (regardless of where it came from) it will be QuickTime that tries to open it. If it's a Quicken file, that of course that will fail.

The thing to do in a case like that is to simply right-click on the file and select "open with". That will allow you to select another program to open that file with. It's just a one-time thing (and you'll need to do it every time for the files that have that extension that's in conflict) but it does allow you to open .qtx files, or any file for that matter, with a program other than the one that has this default association.

Conflicting file extensions

So, ultimately there really is no way to solve it. Different programs simply often use the same file extensions.

There's no central authority. There's no central repository for these kinds of things. Programs choose what they choose. They try and stay out of each other's way but obviously that doesn't always happen.

So, the only thing you can do is choose the default association to be the one, perhaps, that you use the most and use this "open with" technique to open those files in another program when you need to.

(Transcript lightly edited for readability.)

End of Answercast 96 Back to - Audio Segment

Article C6336 - March 4, 2013 « »

Leo Leo A. Notenboom has been playing with computers since he was required to take a programming class in 1976. An 18 year career as a programmer at Microsoft soon followed. After "retiring" in 2001, Leo started Ask Leo! in 2003 as a place for answers to common computer and technical questions. More about Leo.

Not what you needed?


Robin Clay
March 5, 2013 4:08 PM

Or he could rename, say, all the Quicken files with, say, a .QKN extension (or all the QuickTime files with .QKT, say - or do both), and then create that association. Of course, it would be necessary to check first to see that the proposed extension is not already in use. And when saving a new file, it would be necessary to add the correct extension.

March 5, 2013 4:48 PM

Actually, there is a "central authority". It is called the Windows Registry. That is why you can't have 2 programs defaulting to the same file type.

You can add one or both to the "Send To" right click shortcut.

Actually, way back in the days of DOS, when DOS was an operating system rather than a malware attack, you could use any file extension. That was because each program read the "file header", a block of space at the front of the file that contains assorted "housekeeping" information. It is/was simple. One of the PC magazines actually published a very short proof of concept DIY utility that could identify several file types.

MS/Windows moved the equivalent of that functionality to reduce disk reads, speeding up Windows.

Mark J
March 6, 2013 12:09 AM

What Leo meant by no central authority, was that there's no committee which assigns extension names. The registry is a central authority only on your computer. This can be changed be you or a program installed on your computer.

Alex Dow
March 6, 2013 4:43 AM

Could the Registry System and the File Association aspect, be extended that when the first or Primary Associated Program fails to open the file, a Secondary Associated Program tries - ad infinitum?

Billy Bob
March 10, 2013 12:42 PM

How about re-associate that one troublesome extension back to Quicken? Quicktime will still work fine for all the other millions of extensions it associates with. This is a rare one, anyway. Never ran across such a file.

Comments on this entry are closed.

If you have a question, start by using the search box up at the top of the page - there's a very good chance that your question has already been answered on Ask Leo!.

If you don't find your answer, head out to to ask your question.