Log from date of last commit:

LogPluginManager: Loaded Plugin GitSourceControl, From D:/Applications/Epic Games/4.14/Engine/Plugins/Developer/GitSourceControl/GitSourceControl.uplugin
[2018.01.30-01.53.44:729][  0]SourceControl: Info Source control is disabled
[2018.01.30-01.54.17:768][  0]SourceControl: Info On branch master
[2018.01.30-01.54.17:768][  0]SourceControl: Info Your branch is ahead of 'origin/master' by 1 commit.
[2018.01.30-01.54.17:768][  0]SourceControl: Info   (use "git push" to publish your local commits)
[2018.01.30-01.54.17:768][  0]SourceControl: Info Changes to be committed:
[2018.01.30-01.54.17:768][  0]SourceControl: Info   (use "git reset HEAD <file>..." to unstage)
 * * *
[2018.01.31-03.23.13:832][ 69]SourceControl: Info fatal: D:/Applications/Epic Games/4.14/Engine/Content/: 'D:/Applications/Epic Games/4.14/Engine/Content/' is outside repository
[2018.01.31-03.23.14:293][ 69]LogOutputDevice:Error: UE4Editor-SourceControl.dll!SourceControlHelpers::PackageFilename_Internal() [d:\build\++ue4+release-4.14+compile\sync\engine\source\developer\sourcecontrol\private\sourcecontrolhelpers.cpp:52]
[2018.01.31-03.23.14:293][ 69]LogOutputDevice:Error: UE4Editor-SourceControl.dll!SourceControlHelpers::PackageFilenames() [d:\build\++ue4+release-4.14+compile\sync\engine\source\developer\sourcecontrol\private\sourcecontrolhelpers.cpp:103]
[2018.01.31-03.23.14:293][ 69]LogOutputDevice:Error: UE4Editor-SourceControlWindows.dll!FSourceControlWindows::PromptForCheckin() [d:\build\++ue4+release-4.14+compile\sync\engine\source\editor\sourcecontrolwindows\private\ssourcecontrolsubmit.cpp:597]
[2018.01.31-03.23.14:293][ 69]LogOutputDevice:Error: UE4Editor-SourceControlWindows.dll!FSourceControlWindows::ChoosePackagesToCheckInCompleted() [d:\build\++ue4+release-4.14+compile\sync\engine\source\editor\sourcecontrolwindows\private\ssourcecontrolsubmit.cpp:456]
[2018.01.31-03.23.14:293][ 69]LogOutputDevice:Error: UE4Editor-SourceControlWindows.dll!FSourceControlWindows::ChoosePackagesToCheckInCallback() [d:\build\++ue4+release-4.14+compile\sync\engine\source\editor\sourcecontrolwindows\private\ssourcecontrolsubmit.cpp:520]
[2018.01.31-03.23.14:293][ 69]LogOutputDevice:Error: UE4Editor-SourceControlWindows.dll!TBaseStaticDelegateInstance<void __cdecl(TSharedRef<ISourceControlOperation,1> const & __ptr64,enum ECommandResult::Type)>::ExecuteIfSafe() [d:\build\++ue4+release-4.14+compile\sync\engine\source\runtime\core\public\delegates\delegateinstancesimpl.h:1018]
[2018.01.31-03.23.14:293][ 69]LogOutputDevice:Error: UE4Editor-GitSourceControl.dll
[2018.01.31-03.23.14:293][ 69]LogOutputDevice:Error: UE4Editor-GitSourceControl.dll
[2018.01.31-03.23.14:293][ 69]LogOutputDevice:Error: UE4Editor-SourceControl.dll!FSourceControlModule::Tick() [d:\build\++ue4+release-4.14+compile\sync\engine\source\developer\sourcecontrol\private\sourcecontrolmodule.cpp:235]
[2018.01.31-03.23.29:591][ 69]LogSourceControl: FGitCheckInWorker: commit successful
[2018.01.31-03.23.29:687][ 69]SourceControl: Info [master e05ba79] RTS Player Maneuvers Refactoring
[2018.01.31-03.23.29:687][ 69]SourceControl: Info  24 files changed, 0 insertions(+), 0 deletions(-)
[2018.02.01-04.34.49:216][888]EditorErrors:Warning: Warning Failed checking source control status!
[2018.02.01-04.35.03:541][575]EditorErrors:Warning: Warning Failed checking source control status!
[2018.02.01-04.35.20:370][732]EditorErrors:Warning: Warning Failed checking source control status!
[2018.02.01-04.35.41:484][232]SourceControl:Error: Error Failed to enable Git source control. You need to initialize the project as a Git repository first.


From my latest attempt to commit:
[2018.02.04-01.51.00:991][ 78]SourceControl:Error: Error Failed to enable Git source control. You need to initialize the project as a Git repository first.
[2018.02.04-01.51.05:239][579]SourceControl: Info Source control is disabled