When experiencing a browser problem it is often useful to clear the cache. Even after a problem has been fixed you may continue to experience it if the browser is using stored data for quick retrieval.

If you are uncertain how to clear your browser’s cache, please refer to this support article from UI Instructional Technology Services. I recommend getting your browser away from the sites that will not load and from uiowa.edu sites to ensure a new page is downloaded.
Note: In many browsers, there are also options to clear cookies, history, saved passwords and other files. You are welcome to clear whatever you wish, of course, but cache (Temporary Internet Files) is all that is required.

You can also bypass your cache when you reload a page:

Internet Explorer:  Ctrl + reload Mozilla Firefox:  Shift + reload Google Chrome:  Shift + reload Apple Safari:  Ctrl or Shift + reload