Sometimes web applications cannot reach underlying database and report errors or just freeze browser permanently. Re-starting browser sometimes solve this problem, but not always. Problem can be solved by clearing browser cache. This article explain how to do so in Internet Explorer.
Go to “Tools” / “Internet Options”.
In “Internet Options” on “General” Tab, make sure that “Delete browsing history on exit” is Checked, to prevent future problems.
Hit “Delete” button.
On the next screen: check “Temporary Internet files”. Click “Delete”.
Then in previous screen hit "Apply" and "OK".
Re-start your browser and navigate back to the page that was causing problems. If you still having problems, post a comment below.