The Virtual Infrastructure Client used to manage your VMWare ESX hosts may not perform all tasks correctly when running on Windows Vista. There are a handful of issues reported from users in the VMWare communities board such as “Object reference not set to an instance of an object” when trying to use the VMWare cloning features. I was fortunate enough to experience this issue just today. This thread mentions to update some time zone information into the registry. On another Vista system, we performed this registry tweak, and the VI client worked. However, this is not a good resolution from the Vistal environment perspective.
Critical VI Tasks Use on XP
If you are performing some critical VMWare tasks that are prone to failure when the VI client is installed on Vista, a better idea would be to perform those tasks from a Windows XP system. Though the issues reported with Vista are minor, and the VMWare server-side parts have intelligence to manage the issues as they occur to avoid integrity issues with the virtual machines or other pending tasks.
