Virtual Machine Startup/Shutdown grayed out

Hi all,

I'm using vCenter Server 4.1 with 3 ESX 4.1 hosts.

I'm able to click on the Properties option on Virtual Machine Startup/Shutdown, under Host configuration. However, when the windows opens, all options are grayed out. I'm unable to remove nor add virtual machines to/from the Startup/Shutdown sequence.

Can anyone give a hint on how to solve this situation ?

Thanks a lot,

Rui