You can remove IE8 Search Box to not load by default, or remove IE8 Search Box
to load trough GPO.

To change the GPO settings:
1. Go to Start > Run
2. Type gpedit.msc and press OK.
3. Go to User configuration > administrative templates > windows components
4. On the right pane change the "Prevent internet explorer search box from displaying"

You can do manually editing the registry as follow:

1. Start > Run >  RegEdit
2. Navigate to the following registry key:
HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Internet Explorer\InfoDelivery\Restrictions
3. In the right pane, create a new DWORD Value and name it "NoSearchBox data".
4. Set the new value for "NoSearchBox data" to 1.
5. Exit regedit.
6. Close and open IE8.