I shall put these constraints into my worksheet and hopefully will get it working.  I assumed there probably were parameters, I just wasn't sure what they were.  Now I do!

Thank you :)

I think the maximum is for g at it's smallest value and h from 0..2.5E-3, so yeah that's correct.

I've also got an identical problem for the following, slightly different, equation:

"First:=Int(Int(((2*(h-z))/(((((g/2)+L)^2)+(y^2)+(h-z)^2))^(3/2)),y=(-L/2)..(L/2)),z=(-L/2)..(L/2)):
Second:=Int(Int(((2*(h-z))/((((g/2)^2)+(y^2)+(h-z)^2))^(3/2)),y=(-L/2)..(L/2)),z=(-L/2)..(L/2)):
VerB[x]:=(-B[r]/(4*Pi))*(First-Second);"

This should have a single maximum at the smallest g value and h=2.5E-3.

Thanks