SourceTree won't launch external diff

I've used SourceTree in the past to look at diffs with the 'external diff' tool. I was using FileMerge but recently this stopped working. I then followed the instructions to get TextWrangler and KDiff3 installed. Neither of these will launch when I hit the 'External Diff' button. ALthough the configuration will accept me selecting them as my diff tool.

I'm using SourceTree 1.5.6 which the App Store says is the latest version.

3 answers

go to tools git and set it to embedded git and MAKE SURE IT'S UPDATED! Updating it fixed the problem for me!

Worked for me too!

Hi Rafeek,

Just as a quick note, we no longer publish to the App Store due to sandboxing restrictions. The current version is available from which is 1.6.2.

The problem you're experiencing usually happens because SourceTree looks in some pre-specified paths for the application you've stated and can't seem to find it. Do you know what location KDiff3 currently is? If you could tell us that then we could narrow it down to what the problem could be.

Many thanks in advance.

It's installed as an app package in /Applications, the path to the executable is /Applications/

I can launch it successfully by either running it from a Terminal window using that path or by launching it from Finder using the app icon in /Applications

This should work absolutely fine. I've just tested this myself with the same path for kdiff3. The only thing I can think of is that you have some other kdiff3 path that's being picked up which is invalid. Could you run the following at the terminal and copy/paste the output?

locate *kdiff3

This will just find all occurrences of files ending in 'kdiff3' which is the executable. One other thing to try quickly is going into SourceTree, changing the diff tool to something else and closing the preferences pane, then opening it back up again and changing the diff tool back to kdiff3. It may have picked up an old kdiff3 installation.

If that doesn't work then giving me the output as described above will hopefully help us to figure out what's going wrong here.

Many thanks in advance.

Seems to work fine now, nothing has changed other than it's a new day, I haven't even restarted my Mac or done a sleep/wake.

I tried to mark this as answered already but for some reason it didn't take... Maybe this time...

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