Hello my name is XXXXX XXXXX I will be happy to assist you.
A fan failure can be a major issue. The reason is because there are many components in the laptop that get very hot. Without the fan working they will overheat and burnout causing unrepairable damage. The reason the laptop wont start up is because it is trying to prevent this damage.
There is not a lot you can try on your own if you do not have any experience in computer hardware repair for a problem like this because it is not a software issue.
One thing I do suggest you try is a hard reset of the laptop which can sometimes clear an error such as this provided it was just a glitch.
First please turn off the computer and remove the battery and the power adapter.
Once it is completely off press and hold the power button for 30 seconds.
Leave the computer sitting for about 15 minutes with the power adapter and battery out.
Once 15 minutes has passed plug in the adapter but leave the battery out and press and hold the power button for 10 seconds.
If the problem continues after doing that your best bet is going to have it looked at by a professional. You can check if it is still under warranty here:http://h20565.www2.hp.com/portal/site/hpsc/public/wc/home/
Just enter your serial number and country and click submit at the bottom of that page. If it is under warranty follow the instructions on that website to get scheduled for repair.
If it is not under warranty then you will need to find a local computer repair shop and drop the laptop off for repair.
Again a problem like this is best solved in person by a professional and could require the laptop to be disassembled for repair.
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