Repeatedly I have been blocked from certain sites by Firefox questioning the site's certificate. The sites in question are unequivocally trustworthy. I am having this issue with Google, Firefox Help, Amazon Createspace, Dell, and many others that I have visited hundreds and thousands of time in the past. I am experiencing possible hardware problems and I believe this certificate blockage has prevented the Dell technicians from remotely connecting with my computer. My virus programs are up to date and show no virus problems.