A. During the Windows boot process, you can press the F5 key to specify Safe mode or the F8 key to specify boot options. Both keys have 3-byte key-codes, of which the first byte is the same as the Esc key. As a result, if you press Esc, Windows detects this byte and waits for another two bytes (but the key buffer is now empty because Esc is only 1 byte). To remedy this situation, press another key to fill the buffer with extra bytes and let Windows continue to boot.