If you were to use the "Help" menu in IE you would find this:
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To adjust AutoComplete settings
You can configure AutoComplete to save and suggest only the information
you want. You can choose whether to use AutoComplete for Web addresses,
forms, and passwords, or not use it all. You can also clear the history
for any of these.
In Internet Explorer, on the Tools menu, click Internet Options.
Click the Content tab.
Under Personal information, click AutoComplete.
Select the check boxes for the AutoComplete options you want to use.