Failed to install vSphere Web Client 5.1

Hi,

We are running ESXi / vSphere 5.1.  We would like to start using vSphere Web Client.

When we attempt to install it on a Windows 8.1 workstation, it failed with the following error message:

Web client failed to connect to VMware Lookup Service https://<IP address>:7444/lookupservice/sdk

We would like to seek your advice

1) Do we need to install other components on the workstation before installing Web Client ?  If yes, what are components have to be installed ?

2) Does Web Client supports Windows 8.1 ?

3) If it supports Windows 8.1 and no other vSphere component has to be installed, is there any KB that mentions this problem ?

Thanks