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Diagnosing the vSphere/Virtual Infrastructure Client when it fails to connect to vCenter Server/VirtualCenter (1003869)


This article guides you through the process of troubleshooting a situation where you are unable to connect to vCenter Server/VirtualCenter from the vSphere/VMware Infrastructure Client. This article aims to help you eliminate the common causes for your problem by verifying network connectivity, authentication, and permissions.


Validate that each troubleshooting step below is true for your environment. Each step provides instructions or a link to a document, in order to eliminate possible causes and take corrective action as necessary. The steps are ordered in the most appropriate sequence to isolate the issue and identify the proper resolution. Do not skip a step.
Note: If you perform a corrective action in any of the following steps, attempt reconnecting to vCenter Server/VirtualCenter again with vSphere/VMware Infrastructure Client
  1. Verify that you are connecting to the correct hostname or IP address for your vCenter Server/VirtualCenter server. A common reason that connections fail is due to incorrect server information may make the problem seem more complex. Correct any incorrect names, and try connecting to vCenter Server/VirtualCenter again.

  2. Verify that network connectivity exists from the Client computer to the vCenter Server/VirtualCenter. For more information, see Testing network connectivity with the ping command (1003486).

  3. Verify that the VMware VirtualCenter Server Service has not stopped. To do this open the Microsoft Services control and check the status of the service. For more information on starting the vCenter service if it has stopped, see Stopping, starting, or restarting vCenter services (1003895).

  4. Verify that you can connect from the vCenter Server/VirtualCenter to the ESX/ESXi host on port 902 (If the ESX Server was upgraded from version 2.x and you cannot connect on port 902, verify if you can connect on port 905). By default, an ESX/ESXi host listens on port 902 and therefore if the previous steps are all correct it most commonly means that a physical firewall is blocking connectivity on port 902. For more information, see. Testing port connectivity with Telnet (1003487)

  5. Verify that you can connect to the vCenter Server/VirtualCenter on port 443 to confirm if a firewall is configured to allow traffic on this port. For more information, see Testing port connectivity with Telnet (1003487). For a complete list of ports, required by vCenter Server/VirtualCenter, see TCP and UDP Ports required to access vCenter Server, ESX hosts, and other network components (1012382).

  6. Verify that the you are connecting with the proper username and password. Often an incorrect username or password has been specified causing the log on failure to occur. The error message, Login failed due to a bad username or password as shown below is displayed.

  7. Verify that the configured permissions for the account are sufficient to allow for the user to log in to the vCenter Server/VirtualCenter. For more information, see Troubleshooting permissions errors when connecting to vCenter Server with the vSphere Client (1003872).

Note: If your problem still exists after trying the steps in this article, please:

Additional Information

Note: Starting with vSphere 5.5, the vSphere Client is deprecated.


vcenter-server virtual-infrastructure/vsphere

See Also

Update History

02/22/11 - Update to add step 5- 443 port check. 07/24/12 - Updated for 5.x

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