VSphere usage

[phaneendar]

Hi, I am new to VBP(i use VBP7.7a) and need to know the usage of VSphere step. I have metioned the ESX server name (given IP), user, password but still when i am trying to power on a VM i am getting the 'Unable to connect to host. The specific version was not found' error. I can access the VMWare ESX server using the VSphere client installed in my system.The following are the details filled by me
VMware Tab:
Virtual machine: [[ESX2-DS1]] W2k8-R2-V2\W2k8-R2-V2.vmx
gave the OS user name and password and all other fields were blank.
Server Tab:
Host: gave the host IP address here
Host type: ESX/ESXi
port is blank and gave username and password

when i run the program i get the following error:
18-Apr-13 10:41:20 AM: -------------------- Starting Build: 'TestBuild.bld' --------------------
18-Apr-13 10:41:21 AM: Building project step 10 - VMware vSphere...
Unable to connect to host.
Error: The specified version was not found


. I need some help urgently. Thanks.