ws2_32.lib is not included in dm857c.zip is an issue I think.

[Zhouxuan]

The error pops (ws2_32.lib not found) when I compile dub from 
source, the dev environment on my box is setup from scratch, not 
by offical installer/binary package, the libs except 
phobos/druntime are copied from "Digital Mars C/C++ Compiler CD 
Update Version 8.57" 
(http://ftp.digitalmars.com/Digital_Mars_C++/Patch/dm857c.zip).
I think this is an issue, why need I download an offical dmd2 
binary package after successfully build it from source just to 
get this lib?