Reading Time: 2 minutes One possible issue during an upgrade to VMware vSphere 5.1 or 5.5 (but also in a new installation) is related with the introduction of the the SSO (introduced in vSphere 5.1) component in vCenter Server that handle the authentication across the different vCenter Server components, but also against the users. In some cases you may have the following issues during the user autentication: You can log into vCenter Server 5.1 or 5.5 with the vSphere Client or vSphere Web Client only with local users Logging into vCenter Server 5.1 or 5.5 using the vSphere Client […]