I attempted to access "Control Panel -> System and Security -> Administrative Tools -> Local Security Policy" today and received the error:
"an attempt was made to access a token that does not exist"
I'm running as an administrative user, and when I came across this error I was attempting to install Webroot's certificate as a trusted certificate so I could avoid the Blue UAC prompt I receive when my computer boots up and attempts to run webroot. I'd rather it just run.