Update Manager Error: sysimage.fault.SSLCertificateError

I had to redeploy a vCenter Server Appliance recently and got an error when opening vCenter: sysimage.fault.SSLCertificateError.

sysimage.fault.SSLCertificateErrorThis is caused by the certificate on the vCenter Server changing.  This causes the Upgrade Manager needing to be re-registered with the vCenter Server.  Luckily, VMware provides a utility to do just that.  Go to your vCenter Upgrade Manager Server (The appliance does not include this, so it will typically be installed on a separate Windows Server).

Go to “C:\Program Files (x86)\VMware\Infrastructure\Update Manager” and open the file “VMwareUpdateManagerUtility”.

VMwareUpdateManagerUtilityNext, enter the credentials for your vCenter Server and hit Login.

UtilityLoginOnce the window opens, you’ll want to click “Re-register to vCenter Server”. This brings up another login screen.  You can use the same credentials you did to open the utility here as well.

Re-register to vCenter ServerFinally click apply and you will receive a notification that you need to restart the VMware vSphere Update Manager in order for the settings to take affect.

RestartUpdateManagerServiceRestart the service and open the vSphere Client again.  The error will be gone and you’ll be able to use Update Manager again.