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Today i started my macbook pro and after some seconds it stopped working (just turned). I was not able to start it again. After some apple support search I found a page that described how to reset the SMC. After that the notebook startet. Then I switched it of again and tried to start it again but it did not start.

Now every start requires to reset the SMC. Then the notebook boots up.

Any idea what can cause this behavior?

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Did you apply a firmware upgrade recently? – Global nomad Nov 22 '11 at 22:31

Could be the PMU (power management unit) or I think it is now called SMC. Try this:

But do it only once. You could do more bad than good if you do it more than once.

Did you check if there was any firmware upgrade for your MBP?

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I had experienced this with a 2008 iMac. I was also getting kernel panics.

The issue for me turned out to be a dying hard drive. I had previously thought it was bad memory but it wasn't.

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