Many browsers support autocomplete feature, making our life easier. With this feature, browser remembers the input values we make on certain fields e.g. text field and when we go visit the webpage later on, browser make suggestions with those past values we have entered.

Sometimes this is not a desirable feature. Lets say you are on a shared computer and using your credit card to make a purchase. You sure don’t want the computer remember your credit card info.

So how you can turn off or disable autocomplete on a entire web page in asp .net?
Very simple.

<form id="Form1" method="post" runat="server" autocomplete="off">

So how you can turn off or disable autocomplete on a textbox in asp .net?

<asp:TextBox Runat="server" ID="Textbox1" autocomplete="off"></asp:TextBox>

Note that intellisense might not detect autocomplete listed. However it would work just fine if you put that on.

From our Webmaster Forum http://www.webcosmoforums.com/asp/20628-how-turn-off-disable-autocomplete-asp-net.html