The first step is to try charging it for a few hours. Does that work? If not, see if you can try a different battery. In some cases, a bad battery can prevent the BlackBerry from booting up, and batteries can become damaged if exposed to extreme heat or cold.
Also, when you plug your BlackBerry in, do you see a red LED light turn on?
Keep us posted and hopefully we can get you back up and running.
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