Hi,
WCL can work on Win XP, Win XP SP2, Win XP SP3, Win Vista (any), Win 7 (any). It also may work on Win 2000 but not all features are supported. It may work on Win 2003 server and Win 2008 server.
It can run on 64 bit platform but WCL is 32 bit library, We are working on 64 bit version.
.NET 2.0 and above.