Fix Git 'index.lock' File Exists Error in SourceTree - Fix Git Merge Refusing Unrelated Histories-Error 0x80070080002 Windows Update: Step-by-Step Fix

Updated 2026-07-28 05:16:09windows-fixes
Fix Git 'index.lock' File Exists Error in SourceTree - Fix Git Merge Refusing Unrelated Histories-Error 0x80070080002 Windows Update: Step-by-Step Fix
Before changing system settings, save your work and note the exact error text so you can compare results after each step.

Extra verification checklist

  • Restart the affected app after changing permissions or configuration files.
  • Test the same workflow in a clean browser profile or a temporary user account.
  • Compare the result on another network if the error may be connection related.