1. Turn your Sony VGN-TZ170NN laptop over.
2. Find the laptop battery release button lock for your Sony VGN-TZ170NN laptop.
3. Now that your Sony VGN-TZ170NN laptop battery is unlocked, find the battery release button down.
4. Holding the laptop battery release button, gently pull your battery away from the laptop.
5. Now that your Sony VGN-TZ170NN battery is removed, grab your replacement Sony VGN-TZ170NN battery for installation.
6. Insert the battery into the slot. Push the Sony VGN-TZ170NN battery towards the laptop and secure it in place.