(bogus) error messages

dedoimedo just posted some great advice I'd like to re-post, because it's very useful. Besides offering step by step instructions how to handle the
Natty & Nvidia driver not in use error he also advised: what to do, when greeted with an error message:

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What's the lesson of this short howto? First, don't sheep-panic. Second, don't blindly follow online advice. Someone has a similar error message to yours, that does not mean they have the same problem, if at all. In this case, this is clearly a bogus error. But most importantly, you need to know how to approach and troubleshooting issues like this one.

This article teaches you how to follow the train of logic and fix your problems without going overboard with fear or despair or random copy & paste of online solutions. For example, we learned this was a bogus error message.
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So true in so many ways.