Buy some wood filler, the type that uses two tubes that have to be mixed eg the one made by Ronseal. It's strong. When set, drill new holes into the filler to take the screws.
rogdoggydog, December 2010
Remove all loose chipboard. Prime surface with a mix of 50% each of PVA and water. Repair holes with 2 part wood filler. Drill pilot holes to replace hinges.
Big Softy, December 2010
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I can answer this question...
how can I fix my wardrobe doors that have come off leaving big holes ?