Make arrow keys work in visual mode under Windows
From Vim Tips Wiki
On Windows, new users may notice that the arrow keys end visual mode rather than extending the selection.
If this happens, it is because of the
behave mswin line in the default _vimrc installed on a Windows system.
The best solution is to simply remove this line from the global _vimrc, or to create your own _vimrc without it.
However, if you like most of the effects of
behave mswin (see :help behave) and only want to "fix" the visual selection behavior, simply put this into your vimrc after the