I tried to open a file with an extension name of adb in Finder (to be precise, PathFinder). When I clicked the file, vi editor is activated to open the adb file. I didn't do anything with the adb file, so my guess is that vi editor changed the system setup to open it whenever unknown file format is opened.

How can I change this behavior? I want to open TextMate as a default.

2 Answers 2


Check this answer which points you to RCDefaultApp so you can toy with extensions and default apps.


Finder Directions:
Click a file of that type. Press cmd-i. Reveal the Open With: tab of the Get Info window that appears. Select the app you want. Click the Change All button below that menu.

Now, all files of the type you opened will open with the application you selected.

  • 2
    I wanted to know how to open TextMate even though I don't have the setup. I guess there should be some system level configuration necessary.
    – prosseek
    Jan 14, 2011 at 15:09
  • 1
    What do you mean exactly when you say that you don't have the setup? Jan 14, 2011 at 15:13
  • So, you should be able to use the process I described to restore TextMate as the default. You could also check in vi editor's prefs to see if it's got an option for this. Jan 14, 2011 at 15:16
  • 4
    This does not answer the question. Quesiton is about any unknown file type, not a specific one.
    – Ev0oD
    Feb 12, 2020 at 13:03

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .