Boa noite.
Tente fazer via GPO ou faça uma .bat seguindo os passos abaixo:
1:
Hide and Remove IE Search Box via Group Policy Editor
- Run Local Group Policy Editor (GPEdit.msc).
- Navigate to Local Computer Policy -> User Configuration ->
Administrative Templates -> Windows Components ->
Internet Explorer.
- In the settings list in the right pane, locate and double click on Prevent Internet Explorer search box from displaying option. Set its value to
Enabled.

- Click OK.
- Close and re-open IE browser.
- To re-enable and re-display the search box, set the value to Not Configured or Disabled.
Method 2: Disable IE Search Box in Registry
- Run Registry Editor (RegEdit.exe).
- Navigate to the following registry key:
HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Internet Explorer\InfoDelivery\Restrictions
Note: The registry branches starting from Internet Explorer may not be readily available. In this case, manually create the new Key with appropriate names. And if you want user-only restriction, use the HKEY_CURRENT_USER registry branch.
- In the right pane, create a new DWORD (32-bit) Value named as
NoSearchBox data, and set its value data as 1.

- Exit Registry Editor.
- Close and re-open IE browser.
- To add back and turn on the search box in IE 8 again, just delete the NoSearchBox registry key, or set its value data to 0.
Method 3: Prevent IE8 Search Box from Displaying with Registry Registration Files
An easier alternative to method 2, for users of Windows editions without a Group Policy Editor. Just download the following .REG file to patch and fix the registry to hide or show the IE7 or IE8 search box.
FONTE:
http://www.mydigitallife.info/how-to-disable-remove-or-hide-ie8-search-box/
Wallison Francisco Gomes |MCP - MCDST - MCTS - ITILF| Caso a informação seja útil, não se esqueça de pontuar!