Ctrl+Tab is usually used to switch windows using keyboard in Visual Studio IDE:
IDE Navigator has two columns: Active Files column for tabbed windows and Active Tool Windows for tool windows. Selected by default window (stdafx.hpp in the example above) is in Active Files column as Ctrl+Tab corresponds to the Window.NextDocumentWindowNav command. Similar Window.NextToolWindowNav command (without default shortcut) starts with default window selected in Active Tool Windows column. IDE Navigator supports arrow keys (left, right, up, down) and mouse for window selection.
Another command Window.ShowEzMDIFileList with default shortcut Ctrl+Alt+Down Arrow shows alphabetically sorted list of tabbed windows:
In this pop-up window you can navigate using up and down arrow keys, mouse and by typing first letter(s) of window name. For example, typing as selects AssemblyInfo.cpp.