I have an memcached-1.2.1 for win32 originally downloaded from here: http://jehiah.cz/projects/memcached-win32/ (but now for some reason it is a broken link).
This is how I managed to run memcached for Win32 on Windows Server 2008 R2, 64 bit. memcached.exe -> properties -> Compatibility -> Run this program in compatibility mode for: Windows XP (SP 3). Notice that the user Uriel Katz mention in this discussion that this method restricted to 2GB memory of use.