Lyf Wind 7 is a mid-range smartphone that was launched in August, 2016. If you own Lyf Wind 7 and want to connect your device to a computer, then you require ADB driver for your device. Here you will find official driver.
Micromax Bolt D321 was released in 2015, February with Android OS 4.4.2 (KitKat) installed on it. If you are a Micromax D321 user and want the drivers for your device, then you will find official drivers here.