Sansa Express mp3 locked. How to unlock n access the mp3 player?

The lock symbol means that the hold is on. Next to the power button is the hold switch. Make sure the switch is away from the power button so that the red is not showing. If the hold is off and it is still showing the hold symbol, then the hold button may be messed up and may need replacing. But first, do this to check that it isn't just malfunctioning: First, try a soft reset. Do this by pressing the center button and the up volume button simultaneously and try turning it on. If that does not work for you, you will need to get a micro sd card (it can be a dummy) and insert it into the slot on the side of the mp3 player. If you do not have one, you can use one of the round edges of a paper clip (be careful) to get it to come on. When you put either in, it should come on automatically, but if not, just press the power button. This should work.