Note: These steps are for the IE7 browser version, so there could be minor changes in the steps for IE6 or IE8.
Click Start -> Control Panel -> change to Classic View (on left pane) -> double-click Internet Options option.
Go to the Security tab -> Under the “Select a zone to view or change security settings" option -> click Default level button for each icon
Now, Click Programs tab -> click “Make default" button (assuming it’s not grayed out)
Next, you need to Click on Advanced tab -> Under Setting area, click on Restore advanced settings button.
Finally, in the Reset Internet Explorer settings area, you need to Click on Reset button -> Click OK, and you’re done!
Click Apply, and click OK, for the changes to take effect.
Note: If this doesn’t help, you may temporarily disable/uninstall all Anti-Virus programs and firewalls to see if they are causing the problem. If they are causing problems, then you need to contact the corresponding vendor(s) for a solution to the problem.