Installation guide

Upgrade to the vSphere Client
Virtual machine users and vCenter Server administrators must use the vSphere Client 4.0 to connect to vCenter
Server 4.0 or to connect directly to ESX 4.0 hosts.
The VI Client 2.5 and the vSphere Client 4.0 can be installed on the same machine.
The vSphere Client upgrade operation requires no downtime. No virtual machines or clients need to be
powered off for this process.
Procedure
1 (Optional) Use Add/Remove Programs from the Windows Control Panel to remove any previous vCenter
Server client.
Older vCenter Server clients do not need to be removed and are useful if you need to connect to legacy
hosts.
2 Install the vSphere Client 4.0.
If the vSphere Client installation fails, uninstall the vSphere Client using Add/Remove Programs from
the Windows Control Panel. Then reinstall the vSphere Client.
3 (Optional) Install vSphere Host Update Utility.
Install this utility if your environment does not use vCenter Update Manager and you want to use this
workstation to initiate upgrades of ESX 3.x/ESXi 3.5 hosts and manage ESXi host patching.
After you install the vSphere Client 4.0, you can connect to vCenter Server using the domain name or IP address
of the Windows machine on which vCenter Server is installed and the user name and password of a user on
that machine.
If you do not have the VI Client 2.5 installed and you use vSphere Client to connect to VirtualCenter 2.5, the
vSphere Client prompts you to download and install the VI Client 2.5. After you install the VI Client 2.5, you
can use the vSphere Client log-in interface to connect to VirtualCenter 2.5 or vCenter Server 4.0.
What to do next
Use the vSphere Client to connect to the vCenter Server IP address with your Windows login username and
password. Specifically, use the login credentials appropriate to the Windows machine on which vCenter Server
is installed. The vCenter Server username and password might be different than the username and password
you use for ESX/ESXi.
If the vSphere Client displays security alerts and exceptions when you log in or perform some operations, such
as opening performance charts or viewing the Summary tab, this might mean that your Internet Explorer (IE)
security settings are set to High. If your IE security settings are set to High, enable the Allow scripting of
Internet Explorer web browser control setting in IE.
If you cannot connect to the vCenter Server system, you might need to start the VMware VirtualCenter Server
service manually. To start the service, in the Settings menu, select Control Panel > Administrative Tools >
Services > VMware VirtualCenter Server. The machine might require several minutes to start the service.
Using a License Server to Manage ESX 3.x/ESXi 3.5 Hosts
vCenter Server 4.0 does not require a license server to manage ESX 4.0/ESXi 4.0 hosts. vCenter Server 4.0
requires a license server to manage ESX 3.x/ESXi 3.5 hosts.
If you do not have a license server installed and you need one, download the VMware License Server from the
VMware Web site.
The License Server installation requires no downtime. No virtual machines, servers, hosts, or clients need to
be powered off for the installation of the license server.
vSphere Upgrade Guide
56 VMware, Inc.