Source Tree suddenly stopped fetching and pulling from my remote server, but I can successfully push my feature to remote and commit locally. My SourceTree.log in C:\Users\[windows user]\AppData\Local\Atlassian\SourceTree shows ERROR [2018-08-20 18:07:07,309]  [Sourcetree.Installer.Squirrel.Utils.UpdateHelper] [GetSquirrelStagedUserId] - Couldn't read staging user ID. After clicking on FETCH or PULL source tree starts the task but never finishes the action. I really don't know what can I do to solve this problem.
It sounds like an authentication issue? Are you using a private repository, requiring username/password to access? If so where is it hosted?
If you it is hosted in Bitbucket there has been a bug in the Git Credential Manager for Windows which manages the authentication, it might be worth you updating https://github.com/Microsoft/Git-Credential-Manager-for-Windows/releases/tag/v1.17.1
The log message you posted is, unfortunately, not the cause of your problem.
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