Can not log into the monitored account

My laptop runs Windows Vista Home Premium and I have Google Chrome, Internet Exploxer and Safari loaded. I have been using Norton Online family for a while but over the last week the monitored account cannot be logged onto and it says time limit has been reached even though the laptop has not been in use. I have tried to unistall Norton Safety Minder so that I can re-install it but Windows cannot seem to unistall it. Please help