Try this:
Follow these steps (for Windows OS):
1. Click the Tools menu.
2. Select Options.
3. Click the Under the Hood tab.
4. Click Change proxy settings. This opens the Internet Properties dialog.
5. Click LAN Settings.
6. Make sure that the "Automatically detect settings" checkbox is selected.
7. Click OK for all dialog boxes.
(Copied & pasted, not tried personally - I use Firefox.)

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