How to: set your default applications in Mac OS X


One of the most frustrating things in Mac OS X is setting a default application for various file types. Usually the system does this well but sometimes other programs can change default application handling preferences against your wishes. An example of this recently happened to me when I installed Parallels.

For some reason after installing Office 2007 in the Windows environment Parallels started up each time I loaded an Office document as it had changed the Mac Office file associations to point at Office for Windows. Contrary to public opinion I don’t have anything against the new version of Office for Windows (In fact I think it’s one of the best UIs Microsoft has done) but I’d prefer most of the time to stay within the Mac environment for various reasons.

Parallels has since acknowledged that bug and fixed it in build 4560 but it set me thinking about the confusion this unexpected behaviour would cause for users who weren’t intimately familiar with what was going on.

The usual means of changing the application a program uses to open a file is to click on the ‘Open With’ command (under the ‘File’ menu). If you want to change the default program you can also click ‘Other’ select the application and check the ‘Always Open With’ box. Sometimes frustratingly this just doesn’t work.

If you’ve had this problem before you need a System Preference called RCDefaultApp by RubiCode. RCDefaultApp lets you easily set the default application for any file type or extension including UTIs (Uniform Type Identifiers). RCDefaultApp also lets you specify settings for CDs and DVDs web-cams and Digital Camera (even though these can be set through other system or application preferences).


Changing a default application using the Finder

Once installed you can specify default apps by either selecting the application and viewing associated file types or picking a file type and specifying an application. You can even add and delete your own file associations using the ‘+’ and ‘-‘ buttons.


Changing a default application using RCDefaultApp

RCDefault is freeware and works on any Mac with OS X 10.2 and above.