You need to remove the following Windows registry keys using the "regedit.exe" tool. Before you delete them, back up the registry. And please note that I can not guarantee if you have any problems.
HKEY_CLASSES_ROOT\Directory\shellex\ContextMenuHandlers\TortoiseHgCMenu HKEY_CLASSES_ROOT\Directory\Background\shellex\ContextMenuHandlers\TortoiseHgCMenu HKEY_CLASSES_ROOT\Drive\shellex\ContextMenuHandlers\TortoiseHgCMenu HKEY_CLASSES_ROOT\Folder\shellex\ContextMenuHandlers\TortoiseHgCMenu HKEY_CLASSES_ROOT\*\shellex\ContextMenuHandlers\TortoiseHgCMenu HKEY_CLASSES_ROOT\InternetShortcut\shellex\ContextMenuHandlers\TortoiseHgCMenu HKEY_CLASSES_ROOT\lnkfile\shellex\ContextMenuHandlers\TortoiseHgCMenu
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