Yeah it always pops from the birdge

Hi, anytime i restring and tune my custom guitar the B string ALWAYS comes straight off, ALL of the other strings are tuned correctly and so is the B String but it just pops Off. I'm Using Drop D Tunning if that makes any diffrence, Anyone know a fix? thanks

I'd love a schetcher synsyter custom
there so nice and look so gd

I was wondering if installing pickups is hard (its my first time) or if i should go to a shop and ask them to fit them for me i have a Seymour Duncan SH-8 Invader and some iron gear thing
thanks