I have an environment running vCenter 5.5 that we have been using the default administrator@vsphere.local user to login. After installing SSO, I cannot login using either vSphere or the web client. When running it from the vCenter server, vSphere says:
vSphere Client could not connect to [vcenter server name]
An unknown connection error occurred. (The request failed because of a connection failure. (Unable to connect to the remote server))
Web client says:
Failed to connect to VMware Lookup Service https://[server]:7444/lookupservice/sdk - SSL certificate verification failed.
I go to that lookupservice url and it looks good and broke:
<soapenv:Envelopexmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/"xmlns:soapenc="http://schemas.xmlsoap.org/soap/encoding/"xmlns:xsd="http://www.w3.org/2001/XMLSchema"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
</soapenv:Envelope>
I can uninstall SSO and everything's back to normal. Did I miss a step?