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vSphere Client randomly reports the error: An item with the same key has already been added (2030029)

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  • The vSphere Client reports this error intermittently:

    Error: An internal error occurred in the vSphere Client.
    Details: An item with the same key has already been added.

    Contact VMware support if necessary.
    Exception already logged, summary: System.ArgumentException:An item with the same key has already been added.

  • This issue occurs only when the VMware Update Manager plugin is installed and enabled in the vSphere Client


This issue is resolved in VMware vSphere Update Manager 5.0 Update 3 and VMware vSphere Update Manager 5.1 Update 2. For more information, see:

VMware vSphere Update Manager 5.0 Update 3 Release Notes

You can download the latest release from the VMware Download Center.

To work around this issue on other versions of vSphere Update Manager, disable the VMware Update Manager plugin.

Additional Information

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See Also

Update History

11/04/2013 - Added update for VUM 5.0 U3 update 11/09/2012 - Added Update Manager 5.1.x and vCenter Server 5.1.x

Request a Product Feature

To request a new product feature or to provide feedback on a VMware product, please visit the Request a Product Feature page.


  • 49 Ratings

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  • 49 Ratings