On a Windows system, I'm checking for existence of my preferred swap folder with
if isdirectory($HOME . '/.vimswap') == 0 :silent !md \%UserProfile\%\\.vimswap endif
then pointing to it with set directory=$HOME/.vimswap//
set directory=$HOME/.vimswap//
On a Windows system, I'm checking for existence of my preferred swap folder with
then pointing to it with
set directory=$HOME/.vimswap//