Currently, we support the client on Windows 2000. I think it's time to stop doing that. We are not testing on Windows 2000 anyway. Besides, we might want to use APIs etc that are not available on that platform. It's quite old really, no security updates since 2010-07-13.
Fixed in 25569.
Documentations looks cleaned up, grep -ir 2000 didn't came up with anything
putty and tlclient builds defines WINVER=0x0500, which might be something
to change especially for tlclient build ?
Closing this bug, due to the WINVER can/shoudl be as is according to Peter.