Ipopt is indeed broken on Windows: https://github.com/JuliaOpt/Ipopt.jl/issues/77. @tkelman has thankfully gotten to the root of the issue, but the fix is not released at the moment. See that issue for further discussion.
Ipopt is indeed broken on Windows: https://github.com/JuliaOpt/Ipopt.jl/issues/77. @tkelman has thankfully gotten to the root of the issue, but the fix is not released at the moment. See that issue for further discussion.