If U can't get it out U may have to drill it out and re tap the thread - how to do! Remove the part to make it easier.
Don't ya just love it when an easy job becomes a pain in the ass! hehehe
If U don't wanna do the above get the car or car part to someone who has experience,good mechanics always have tricks to sort these problems out quick smart.
He's trying to remove a philips head screw, not fix a messed up thread.
I reckon the wrong screw driver size was used, hence the head was messed up. Happens often with philips head screws. I'd use an easy-out and then replace with a proper hex-head bolt if it takes a standard metric thread.
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