After updating the SDK, Eclipse shows this error:
ADB server didn't ACK, failed to start daemon.
Please ensure that adb is correctly located at 'D:\android-sdk-windows\platform-tools\adb.exe' and can be executed.
I have solved my first question: Open Eclipse, open the SDK Manager, and choose the device to open.
Or you can open the SDK directory. Open the SDK Manager, and then choose the device to open
2: Close Eclipse, and then open it.