Come for the products,
stay for the community

The Atlassian Community can help you and your team get more value out of Atlassian products and practices.

Atlassian Community about banner
Community Members
Community Events
Community Groups

SourceTree failed to start

Please help!

On Windows 10, SourceTree wasn't opening anymore, so I removed the software and deleted the Atlassian folder in my users/AppData/Local folder, then downloaded and reinstalled SourceTree v. Same problem.

I found the sourcetree.log file, and this is what it contains:

ERROR [2017-09-19 09:28:53,181] [1] [SourceTree.App] [.ctor] - finish EnsureSquirrelExecutionStubIsCopied
ERROR [2017-09-19 09:28:53,306] [1] [SourceTree.App] [OnStartup] - Failed to start
System.NullReferenceException: Object reference not set to an instance of an object.
at SourceTree.Notifications.NotificationsManager.SetOwner(NotificationDialogWindow notificationWindow)
at SourceTree.Notifications.NotificationsManager.ShowNotificationDialog[T](NotificationDialogWindow notificationWindow, Tuple`2 customAction, VistaTaskDialogIcon icon)
at SourceTree.Notifications.NotificationsManager.ShowNotificationDialog[T](String title, String message, Tuple`2 customAction, String cancelLabel, String suppressionSetting, Action`1 suppressionChangedAction, Object contentControl, String contentCommandLabel, Action contentAction)
at SourceTree.Notifications.NotificationsManager.ShowNotificationDialogWithYesConfirmation(String title, String message, String details)
at SourceTree.Configuration.WpfSpellCheckerPreFlightCheck.Run()
at SourceTree.AppRoot.RunPreFlightChecks()
at SourceTree.AppRoot.OnStartup(StartupEventArgs e)
at SourceTree.App.OnStartup(StartupEventArgs e)

10 answers

2 accepted

22 votes
Answer accepted
Mike Corsaro Atlassian Team Sep 19, 2017

Hello! This is a known issue. Please navigate to the config file location (C:\Users\{USERNAME}\AppData\Local\Atlassian\SourceTree.exe_{RANDOM_GUID}\\user.config) and find the following line:

<setting name="AutomaticallyCleanUpDictionaryFiles" serializeAs="String"> 

Make sure that value is set to True

I had to add this setting, as it was not present probably due to reinstalling to try to fix the problem.  But adding the setting fixes it.  The installer was not even running without this setting.

That did it! I'm glad it was a simple as that. 

Thanks much!

Thank god! That was it. Worked instantly after adding the setting and running sourcetree again.

This worked.

Can you had this into the installer and make a new version ASAP.   Its really frustrating as there is not UI on the installer (really bad idea) or the application with this error.   And lots of threads with installer/load issues.   Took me a while to find this.

No such line. Plus, I don't really like this way of doing things. Basically, you are asking users to delete something that they don't want to.



You don't delete it, you add it.

That worked, although I now need to re-add all my projects since I followed other advice on this forum and deleted the apps folder.

I'm disappointed,  it's over a week since it was reported and a fix found, I would have expected a new installer to have already been out that fixed it.

Thanks, I've been searching for this. And i got fixed.

Thanks Mike but I can't believe that a mature software has such major problems that it doesn't even start.

Why can't they write working code?

Took me quite a while to find this after sourcetree just stopped working. Finally fixed it thanks.

This is not easy enough to find for a known issue.

Whoa what a fix. I hope they can have a real fix for these. I almost reinstalled my windows vm. 

Ran the installer (v2.3.1.0) on Win10 and it seems nothing happened, however, the app was actually installed. When trying to run the app I'd see the sourcetree.exe process for about 5 seconds and then it'd go away. Once I added that setting to the user.config the app worked fine. No reinstall was needed.

Did the job. Thanks!

So, this worked for me.  Downloaded a brand new installer this morning and it is STILL not fixed in the installer.  I blew away an hour of my time trying to get this thing to load.  

I work on a small software team and we frequently have some QC issues like this as well.  THIS makes me feel a lot better about my own product and QC processes!

this did not work for me.  when I found the user.config file, I found it was corrupt.  parsely formatted XML with jibberish at the end.   No idea how it got that way.  I copied user.config from a previous folder and then I was able to open SourceTree 2.3.1

1 vote
Answer accepted
Ana Retamal Atlassian Team Oct 19, 2017

Hi everyone! As an update, we've started the progressive rollout of Sourcetree v2.3.5.0 which includes a fix for this issue. You should be prompted to upgrade at some point over the next 14 days or, alternatively, you can download it directly from

Cheers :)



Can you explain why SourceTree installs in the user appdata folder rather than program files folder like most windows apps?  I find this very strange.

// SourceTree.Notifications.NotificationsManager
private static void SetOwner(NotificationDialogWindow notificationWindow)
    Window currentWindow = WindowsOSHelper.GetCurrentWindow();
    Window window = (currentWindow == notificationWindow) ? null : currentWindow;
    if (window != null && window.IsVisible)
        notificationWindow.Owner = window;
    NotificationsManager.Logger.Error(string.Format("Unable to set owner as parent {0} is not visible", window.Name)); // <- Problem's here. If windows == null. It's not going to work.

Same bug for me. No workaround works.

Amazing. I lost 2 hours today with this. 

None of the above solutions worked for me.  Tried a clean install of 2.3.5 after deleting all %localappdata%.  Same error... [ERROR [2017-11-08 15:53:23,111] [1] [SourceTree.App] [.ctor] - finish EnsureSquirrelExecutionStubIsCopied]

Wasted too many hours on this, now moving to alternative product.

I'm in the same doom loop. What did you switch to?

I'm in the same situation. I tried many products, but nothing was better than Sourcetree. I hope SourceTree dev team investigate this issue seriously...

OMG! Can you just fix this problem in new version?

For searching solution I'm lost all settings...

Merci beaucoup.
Arrêtez de pleurer alors que vous ne payez même pas le logiciel !!!

It works for me, I added to the file 

<setting name="AutomaticallyCleanUpDictionaryFiles" serializeAs="String"> 

Thanks! Adding this setting solved for me (Win 10 16299.15, SourceTree!

Hi @Nicolas Frelat,

If you do have the same call stack in you log file, here's the other way to fix the issue:

1. Open RegEdit. Navigate to:

2. Computer\HKEY_CURRENT_USER\Software\Microsoft\Spelling\Dictionaries

3. Double click the "_Global_"

4. Check each file and see if they exists.

5. Remove the one that's not there.

6. Hit OK.

7. Start your SourceTree.

There's another solution provided by @Mike Corsaro might also be working. However:

1. You might be scared, as I was, by both the popup message or the setting name "Remove the dictionary files" or "Cleanup dictionary files". In fact, it's not going to remove any file but the path of the non-existing file in the registry if you read the source code.

2. You might find that there is no such "AutomaticallyCleanUpDictionaryFiles" in the user.config file on your local machine. And you entered the panic mode because the file is huge and you don't know where would be the right spot to put it in as I did.




Not sure why they think the missing files will causing the slowness. Maybe it's about the network issue. However, I don't really like the way it is now which confuses users a lot. It should:

1. Measure the time of loading the dictionary files and ask users if they like to not loading these files if it's too slow. Trying to load a missing file on local machine should not be taking too long, especially compared with the time asking user to read the popup and think about why I have to do that. Or,

2. Lazy loading the files asynchronously. It should not be affecting the core feature even if some of the files do not finished loading on time. Or,

3. At least fix the message to not scare the user but tell the truth. It's not cleaning up the files. The files are not corrupted. It's just prevent check and loading the non-existing files only.


The registry edition tip did the job! After the change, I had some more glitches but now it works.

Thank you.

Suggest an answer

Log in or Sign up to answer
Community showcase
Published in Sourcetree

Bug Fix: Sourcetree for Windows authentication error when updating to app password

Hello Sourcetree users!!! With the recent removal of Bitbucket Cloud account passwords for app passwords (please see our Bitbucket Cloud community post for details on why we made this change for se...

62,288 views 127 27
Read article

Community Events

Connect with like-minded Atlassian users at free events near you!

Find an event

Connect with like-minded Atlassian users at free events near you!

Unfortunately there are no Community Events near you at the moment.

Host an event

You're one step closer to meeting fellow Atlassian users at your local event. Learn more about Community Events

Events near you