When turn on MacBook air the screen is blue.I can't get into any icons.

Try to reset your SMC (System Management Controller) p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 12.0px Helvetica; color: #1a1a18}
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1. If computer is on, turn it off by choosing Shut Down from the Apple menu.

2. Connect power adapter to computer and to a working power source.

3. On built-in keyboard, press (left-side) Shift-Control-Option along with power button just once. Important: Use Shift-Control-Option keys on left side of keyboard.

Note: When the LED on the MagSafe connector is orange/amber, resetting the SMC will change it to green for a few seconds, indicating that SMC was correctly reset.

4. Wait 5 seconds and press power button to start computer.

If it starts without beeping errors reset the PRAM (Parameter RAM)

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1. If computer is on, turn it off by choosing Shut Down from Apple menu.

2. Locate the following keys on the keyboard: Command, Option, P, and R. You will need to hold these keys down simultaneously in Step

4. Note: If keyboard does not have an Option key, use Alt key instead.

3. Press power button.

4. Immediately press and hold Command-Option-P-R keys.

Important: You must press this key combination before the gray screen appears.

5. Hold down keys until computer restarts, and you hear startup chime a second time.

6. Release keys.

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