“You must specify a value for this required field” error - SharePoint 2010

Step 1

Create a  CSS class called hiddenpanel:

.hiddenpanel
{
  visibility:hidden;
}

Step 2

Add following code in the MasterPage:

<asp:Panel runat="server" CssClass="hiddenpanel">
  <h2>
        <asp:ContentPlaceHolder id="PlaceHolderPageTitleInTitleArea" runat="server" />
   </h2>
</asp:Panel>