John; If you have problems, the first thing to do is run an anti-virus scan of your PC. MalWareBytes is a good one and has a free option. It will tell you if you have a virus or other mal-ware. You will need the paid version to clean the offensive software from your machine.
One final option is to unplug (NOT turn off, UNPLUG) your Internet Router and your computer. Leave them off for about 20 minutes then plug them back in. Router first, wait 5 minutes, then computer.
I will send you a PM.
Techy-Dweeb: Web site names are kept on a set of internet servers called DNS. This is a cross reference that has the actual internet address of internet machines and their matching NAME. Whenever your machine asks to connect to say "penturners.org" the DNS server will send your machine the actual Internet Address like "192.168.1.10" (fake address). These machines routinely sync with each other sharing changes to the list. ISPs like AOL, Verizon, Comcast sometime have their own copies of the DNS list. If the list is wrong or corrupt it can take several days to correct itself.