Here are some solutions to this problem:
1. Delete temporary internet files and cookies
2. Turn off all add-ons on your browser. If this works, then you can turn them back on one at a time to find out which one is causing the problem.
3. Check to see if any third-party program or pop-up blockers may be blocking the site.
4. Reboot your computer.
5. Reboot your modem by unplugging it for one minute, then plugging the modem back in.