Windows 10 windows search bar only gives a black box..help

This should fix it:

1: Open regedit; Navigate to Computador\HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Search

2: Set "BingSearchEnabled" to 1 (create it as a DWORD if it does not exist).

3: Open your Task Manager and kill the Cortana process (so it restarts and reloads that setting from the registry).

This might solve the problem!