Shift key shuts down my computer

Starting up in Safe Mode Follow these steps to start up into Safe Mode.

1. Be sure your Mac is shut down.
2. Press the power button.
3. Immediately after you hear the startup sound, press and hold the Shift key. The Shift key should be pressed as soon as possible after startup, but not before the startup sound.
4. Release the Shift key when you see the Apple logo appear on the screen.

After the Apple logo appears, it may take longer than usual to reach the login screen. This is because your computer is performing a directory check as part of Safe Mode.
To leave Safe Mode, restart your computer without pressing any keys during startup.

• Log on to the Presario 2100 and click the "Start" button. Choose "Shut down" from the menu and confirm the shutdown at the next screen. Wait for the computer to shut down completely.
• Press the "Power" button on the front of the computer. Wait until the screen goes blank, then press the "F10" key to enter the setup menu.
• Press the right or left arrow key to highlight the "Advanced" menu. Arrow down to the "Boot Order" option.
• Highlight "USB Devices" and press the up arrow until it is at the top of the boot order. Press the "F10" key to save the settings and exit the setup menu.

Try removing the AC power, removing the battery and then holding down the power button for five seconds. On the MacBook Air, press (left) Shift-Control-Option along with the power button once. Note: You must use the keys on the left side of the MacBook Air keyboard.
If that doesnt work try this:

1. Shut down the computer.
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.
3. Turn on the computer.
4. Press and hold the Command-Option-P-R keys. You must press this key combination before the gray screen appears.
5. Hold the keys down until the computer restarts and you hear the startup sound for the second time.
6. Release the keys.

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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Welcome.

First of all, make sure that the application meets the system requirements.

Restart the computer by choosing Apple Menu - Restart. Also you can try to Restart in Safe Mode.

To Restart in Safe Mode:

1. Shut down your computer and wait 10 seconds.
   

2. Press the power button.
   

3. Immediately after you hear the startup tone, hold down the Shift key.
   

   You should press the Shift key as soon as possible after you hear the startup tone, but not before.
   

4. Release the Shift key when you see the gray Apple logo and progress indicator (spinning gear).
   

Hope this helps!

To start up in safe mode:

Shut down your computer and wait 10 seconds.

Press the power button.

Immediately after you hear the startup tone, hold down the Shift key.

You should press the Shift key as soon as possible after you hear the startup tone, but not before.

Release the Shift key when you see the gray Apple logo and progress indicator (spinning gear).

***Using the Start Menu

• Press a Windows key (the ones with the Windows symbol on as shown right), this will open up the Start Menu.
• Use the cursor keys (the ones with arrows on) to highlight 'Turn off Computer' and press Enter to select it
• A dialog box will open. Use the cursor keys to to highlight 'Shutdown computer', 'Turn off' or whatever your version of Windows says, and press Enter again.

***Using the 'three finger salute'
Hold down Ctrl and Alt, and press Delete.
Windows 2000 and XP Home Edition users will be presented with a dialog box with buttons on:

• · Use the cursor keys to select the 'Shut Down' button and use Enter to select it.
• · Select 'Shut down' from the list using the cursor keys and press Enter one more time.

In other versions of Windows the Task Manager will open:

• · Hold down Alt and press U to open the 'Shut Down' menu.
• · Use the cursor keys to highlight 'Turn Off' and press Enter.

***Hit Alt F4 'till you can't any more
The final method of shutting down that I will explain here is to hold down the Alt key and press F4 repeatedly. This will close every application that is open on Windows and eventually will close Windows itself. You may be asked if you want to save files by some programs, if so use the cursor keys and Enter to get past these dialog boxes.

Sounds like you need to reset your SMU and NVRAM:

To reset your SMU:

1. Turn off the computer by choosing Shut Down from the Apple menu, or by holding the power button until the computer turns off.
2. Unplug all cables from the computer, including the power cord.
3. Wait 10 seconds.
4. Plug in the power cord while simultaneously pressing and holding the power button on the back of the computer.
5. Let go of the power button.
6. Press the power button once more to start up your iMac.

To reset your NVRAM:

1. Shut down the computer.
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.
3. Turn on the computer.
4. Press and hold the Command-Option-P-R keys. You must press this key combination before the gray screen appears.
5. Hold the keys down until the computer restarts and you hear the startup sound for the second time.
6. Release the keys.

If those don't resolve the issue, your computer will probably need service. Good luck!

1. Shut down the computer.
2. Unplug all USB devices other than a keyboard.
3. Start up the computer. When the brand logo appears, press the F2 key to enter the System Setup (BIOS) program. If the Windows screen appears, wait until the computer finishes starting up, then shut down and try again.
4. Press the Down Arrow key to highlight Integrated Devices (Legacy Select Options).
5. Press the Enter key.
6. Press the Down Arrow key to highlight USB Emulation .
7. Press the Space Bar until the option displays No BOOT .
8. Press the Esc key twice to go to the Exit menu.
9. Ensure that Save Changes and Exit is highlighted, and press the Enter key.

1. Shut down the computer.
2. Unplug all USB devices other than a keyboard.
3. Start up the computer. When the brand logo appears, press the F2 key to enter the System Setup (BIOS) program. If the Windows screen appears, wait until the computer finishes starting up, then shut down and try again.
4. Press the Down Arrow key to highlight Integrated Devices (Legacy Select Options).
5. Press the Enter key.
6. Press the Down Arrow key to highlight USB Emulation .
7. Press the Space Bar until the option displays No BOOT .
8. Press the Esc key twice to go to the Exit menu.
9. Ensure that Save Changes and Exit is highlighted, and press the Enter key.