INTONATIO PROBLEM URGENT HELP NEEDED

[harmonix]

ive just restrung my fixed one piece bridged guitar and every thing is ok exept that the high e when played open plays an e butwhen played at the 12th fret plays an f and when played at the 24th plays a g.ive tried altering the string length via the bridge saddles but its making little to no difference what should i do?please help ive got band practice in an hour!

[Dimebag]

check the nut and the bridge carefully, there could be something in them affecting it. Have you changed string guages? This sort of things wouldnt really happen for no reason, try to think what you have done differently