I had to open the laptop and found the fan was off its mounting points. Lucky on that one (remember I work on hundreds of laptops a year so I won't retell all the stories) and after it was put back in place, I gave the inside a quick clean with canned air then it was "like nothing had ever happened."
Just 150USD on the bill, no parts and cheaper than a new laptop.
2 days ago my HP Notebook 2000 (Windows 10) began making a loud whirring noise- later in the day after I opened it instead of going to the login page it got stuck on an orange screen with a spinning wheel. After I turned it off manually then on again it got to the hp page, followed by a dark screen; in later attempts it sometimes got to the orange screen, but never to the sign in page. I tried a hard reset, then BIOS recovery, neither of which made any difference.
Finally I used compressed air on the vents thinking maybe too much dust had accumulated; after turning it on again I got a 90b error ('The system has detected that a cooling fan is not operating correctly') and again was unable to start Windows. Is it possible I damaged the fan (or damaged it more than it already was) in trying to dust the vents? Does anyone have any ideas about next steps (other than just taking it in for repair)?

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