Remove OneDrive from the File Explorer Sidebar in Windows 10

1. Regedit
2. HKEY_CLASSES_ROOT\CLSID\{018D5C66-4533-4307-9B53-224DE2ED1FE6}
3. You’ll see a DWORD entry labeled System.IsPinnedToNameSpaceTree set to a value of 1 (one). To remove OneDrive from File Explorer in Windows 10, go ahead and double-click on that DWORD and set its value to 0 (zero).
4. Click OK to save your changes and then close the Registry Editor.
5. Restart computer

Source: https://www.tekrevue.com/tip/remove-onedrive-file-explorer-sidebar-windows-10/