Whenever I try to acces any site that has https I get 'Cannot find server or DNS error'. I've tried turning the firewall off, adding port 443 to it, turning pop up blockers off, running ad aware and spybot s&d, deleting cookies, TIF files, and clearing history with no luck. I tried telnet localhost 443 in the command prompt and got back 'Could not open connection to the host, on port 443: Connect failed'. Any suggestions? Is it my router causing the problem?

Open IE and click Help, About Internet Explorer and look at the Cipher Strength. It should be 128 bit. If the Cipher Strength is anything less then 128-bit, download and install the Internet Explorer High Encryption Pack.

Open IE, go to Tools, Internet Options, Advanced and scroll to bottom of list. The SSL and TLS options (all versions) should be checked.

I already checked those things out. Any other suggestions? I did have a browser hijacker on the computer a couple months ago, and I'm not sure if I totally got rid of everything.

Do you have any other browser? check if the secure sites open in the other browser...

I also have Firefox, but I get the 'Problem loading page' screen with 'The connection was reset'. I can get into some secure sites. I can log in to amazon.com and bestbuy.com through https, but I can't get on other secure sites (can't log in to espn.com nor my on line banking site).